Issuu

Rise of Nesi

When beneficial turns greenhouse pest | 16

CGC ‘26 preview A sneak peek at the 2026 Canadian Greenhouse Conference | 26

Steamed up Heat treatments set strawberries up for IPM success | 36

SEPTEMBER 2026

BIOCONTROL IN FOCUS

greenhousecanada.com

FROM DESIGN TO BUILD

DeCloet’s team of dedicated professionals bring over 4 decades of experience to each project. With proven success in numerous installation projects we know we can put your mind at ease.

DecloetGreenhouse.com 519-582-3081

CONTENTS

PHOTO: SUPPLIED

September 2026

Vol.46, Issue 6

New reality

Navigating Canadian floriculture’s changing landscape. 4

Industry News

CGC preview

Petal pioneer Profiling She Grows honouree Janis Harris.

Events

Inside View

50 PHOTO: SUPPLIED

Editorial

PHOTO: MOHYUDDIN MIRZA

16 36 ON THE COVER The samurai wasp (Trissolcus japonicus) is a potential biological control agent for invasive stink bugs in greenhouses. READ MORE on Page 8. Photo: Warren Wong.

Mirid divide

Hot seat

Disease triangle

How to address the widening gap between beneficial and problematic mirids.

Steam‑treated transplants give greenhouse strawberry IPM a major edge.

Host, pathogen and environment collide when humidity spikes, airflow drops and stress builds.

BY ISABELLA NARDONE

BY KARLI BARTON

BY MOHYUDDIN MIRZA

FROM THE EDITOR

GREENHOUSE CANADA is the only national business magazine published exclusively for the commercial greenhouse grower in Canada.

AMY KOUNIAKIS

September 2026 - Volume 46, No. 6

Balancing the season ahead It’s become apparent to this industry newcomer that greenhouse growing is equal parts science and stamina. Pests don’t take breaks, markets never co-operate, and growers are always adjusting to keep crops on track in the face of a changing climate and an increasingly uncertain business landscape. What astonishes me is how easy it seems to look from the outside, but in reality, it’s a constant negotiation between a number of incompatible forces that leave little room for error. Every season comes with its own complex set of challenges, every crop cycle adding new pressures onto the last as growers navigate shifting pest behaviour, emerging pathogens, unpredictable weather patterns, tariff threats, policy changes, risings costs and the need to stay one step ahead of whatever shows up next.

and resilience the industry demands; someone who understands firsthand how every decision, every experiment and every recalibration contributes to keeping crops moving forward. That balancing act is also supported by a steady flow of events, learning opportunities and dialogue that keep the industry moving. The Canadian Greenhouse Conference (CGC), now just weeks away, remains one of those annual traditions where growers can step out of the day‑to‑day and into a space built for learning, questioning and sharpening the decisions they make back home. It’s a place where research meets practice, where growers can compare notes on emerging pressures, and where new ideas often find their footing. In a year defined by unpredictability and uncertainty, the

“It’s a balancing act that demands both instinct and intention...” It’s a balancing act that demands both instinct and intention, as growers juggle competing priorities and make tough calls about where time, labour and resources will have the greatest impact. Some decisions are made in the moment while others require long‑term planning and a willingness to rethink what’s possible. The work is both reactive and proactive, grounded in experience but shaped by whatever new pressure emerges next. In this issue, you’ll find stories that help inform that balance; innovation like steam-based IPM, new insights into mirids and stinkbugs, a closer look at wilt and its causes, and a frank assessment of floriculture’s fluctuations. You’ll also meet a grower whose work reflects the adaptability 4 GREENHOUSE CANADA - September 2026

value of this year’s gathering feels especially poignant. Starting on Page 26, we feature a preview of what’s to come at this year’s CGC. The months ahead will bring their own mix of challenges and opportunities, but growers aren’t facing them in isolation. With fresh innovations, shared insight and a community that continues to learn from one another, Canada’s greenhouse sector is better equipped than ever to handle what comes next. It’s my hope that Greenhouse Canada and some of the stories in this issue offer a moment of clarity, inspiration or a new perspective or tool that will help steady some of the decisions growers will have to make in the near and distant future.

Reader Service Print and digital subscription inquiries or changes, please contact Angelita Potal, Customer Service Tel: 416-510-5113 Email: apotal@annexbusinessmedia.com Mail: 111 Gordon Baker Rd., Suite 400, Toronto, ON M2H 3R1 Editor AMY KOUNIAKIS akouniakis@annexbusinessmedia.com 519.429.5203 Publisher NASHELLE BARSKY nbarsky@annexbusinessmedia.com 905.431.8892 Account Coordinator KATHRYN NYENHUIS knyenhuis@annexbusinessmedia.com 416.510.6753 Audience Development Manager SHAWN ARUL sarul@annexbusinessmedia.com 416.510.5181 Group Publisher & VP, Content Strategy MICHELLE BERTHOLET mbertholet@annexbusinessmedia.com CEO SCOTT JAMIESON sjamieson@annexbusinessmedia.com Media Designer BROOKE SHAW Publication Mail Agreement #40065710 Printed in Canada ISSN 0712-4996 SUBSCRIPTION RATES Canada - 1 Year $41.37; Single $6.00 (plus applicable taxes) U.S.A. - 1 Year $94.41 CAD Annex Privacy Officer Privacy@annexbusinessmedia.com Tel: 800-668-2374 GST - #867172652RT0001 Occasionally, Greenhouse Canada will mail information on behalf of industry-related groups whose products and services we believe may be of interest to you. If you prefer not to receive this information, please contact our circulation department in any of the four ways listed above. No part of the editorial content of this publication may be reprinted without the publisher’s written permission. ©2026 Annex Business Media. All rights reserved. Opinions expressed in this magazine are not necessarily those of the editor or the publisher. No liability is assumed for errors or omissions. All advertising is subject to the publisher’s approval. Such approval does not imply any endorsement of the products or services advertised.

greenhousecanada.com

INDUSTRY NEWS greenhousecanada.com

‘Clean start’ method effective against T. Parvi: study New research from Vineland Research and Innovation Centre is providing clearer guidance on ‘clean start’ treatments for Thrips parvispinus on imported tropical cuttings. According to research recently shared on ONFloriculture.com, trials showed various Beauveria‑based dips delivered up to 97 per cent reduction in larvae, while combinations improved control across both eggs and larvae. Phytotoxicity remained low across most tropical hosts tested, though some products caused more damage at higher rates. The research, authored by Vineland’s Ashley

Summerfield (M.Sc.), also highlights two promising dip alternatives: cold treatment at 3°C for three days, which cut survival by up to 100 per cent in adults, and steam‑heat treatment at 44°C and 100 per cent RH, which achieved near‑complete mortality across all life stages. Summerfield points out that while both methods showed strong results on whole plants, though equipment access remains a barrier. Growers are urged to test all treatments on a small batch first, as sensitivity varies widely by crop and conditions. (Source: ONFloriculture.com)

‘CONSUMERS CAN BE CONFIDENT’: OGVG RESPONDS TO FOOD‑SAFETY CONCERNS

PHOTO: ROMASET/GETTY

The Ontario Greenhouse Vegetable Growers (OGVG) reaffirmed its commitment to food safety, traceability and transparency amid heightened consumer concern fuelled by the ongoing outbreak of a diarrhea-causing parasite linked to iceberg lettuce in the U.S. In a statement issued after the Windsor-Essex County Health Unit (WECHU) reported an uptick in the number of reported cases of

cyclosporiasis among individuals who recently travelled to Michigan, the association sought to reassure consumers of the safety of greenhousegrown produce. “Consumers can be confident in the safety of Ontario greenhouse vegetables,” said OGVG executive director Richard Lee in the statement. “Our growers operate under some of the most rigorous food safety and regulatory requirements in North America.”

Ball locks in major tropical acquisition Ball Horticultural Company has announced a significant expansion of its tropical category, with the acquisition of Aris Horticulture’s Tradewinds Hibiscus genetics and key portions of its tropical commercial business. As of early August, Ball FloraPlant took ownership of the full Tradewinds Hibiscus portfolio, introductions and the Tradewinds trademark. The company says the addition strengthens its genetics offering and supports continued innovation in tropicals. On the distribution side, Ball Seed will assume commercial responsibilities for Aris’ tropical liner, prefinished and finished programs. (Source: Ball Horticultural Company) 6 GREENHOUSE CANADA - September 2026

The OGVG statement goes on to clarify that greenhouse-grown tomatoes, peppers and cucumbers are produced in controlled indoor environments that limit exposure to common contamination sources such as open soil, rain, runoff and wildlife. It also notes commercial greenhouse operations are subject to annual third‑party food safety audits recognized by the Global Food Safety Initiative (GFSI).

Growers are also required to meet federal regulatory requirements and the food-safety expectations of major retailers and foodservice buyers across North America. “Food safety is a shared responsibility from greenhouse to table,” said Lee in the release. “We remain committed to earning consumer trust through safe, reliable, and transparent production practices.” (Source: OGVG, Windsor-Essex County Health Unit)

BY THE NUMBERS

Source: ‘Canada’s greenhouse boom is growing output, but not domestic availability,’ FCC Economics; July 2026.

Nearly three out of every 10 fresh vegetables produced in Canada come from a greenhouse

Greenhouse vegetables generated roughly $460M more revenue than field vegetables in 2025.

INTRODUCING

SUNPATIENS The SunPatiens for container gardening

PETITE

The latest innovation in the SunPatiens® series, a miniature SunPatiens ideal for containers and hanging baskets Use in 7-12” containers Includes 5 vibrant colors Maintains dense, bushy habit all summer long for superior customer satistaction No PGR needed

Scan me!

for additional product information

SAKATAORNAMENTALS.COM

PHOTO: WARREN WONG

Stink bug surge An update on stink bugs in British Columbia greenhouses

BY PAUL ABRAM

Since at least the early 1990s, a handful of native species of stink bugs have been sporadic pests of greenhouse peppers. I last wrote about stink bugs in B.C. pepper houses for Greenhouse Canada in 2019. Since then, there have been increasing problems with two new invasive stink bugs, one of which is now relatively widespread in B.C. pepper houses. Invasive stink bugs have also recently been reported in greenhouse cucumbers and strawberries in the province and have the potential to become an issue in tomatoes as well. In this ‘update,’ I will focus on peppers, for which there is currently the most information available. STINK BUG LIFE CYCLES Stink bugs progress through an egg stage, five nymph stages, and an adult stage. Eggs are laid in clusters, varying in the number, depending on the stink bug species. Nymphs do not feed in their first

stage (instar). Second through fifth-instar nymphs do feed and cause damage to plants, including plant growing tips and fruits at various stages of maturity. Adult stink bugs are long-lived (several months) and, unlike nymphs, can disperse by flying. All stink bug species found in B.C. pepper houses have one generation per year, starting in the spring with the adult stage and ending in the fall with their adult offspring. STINK BUG DAMAGE TO GREENHOUSE PEPPERS Stink bug feeding on pepper fruit causes light ‘blotches’ that can be seen on the skin of the pepper but penetrate down deeper into the fruit tissue (Figure 1). Even a few such blotches render a pepper fruit unmarketable. A few growers have reported >15 per cent yield losses due to stink bugs in some years.

ABOVE The samurai wasp (Trissolcus japonicus) lays its eggs inside stink bug eggs, and the development of its offspring kills the developing stink bug. In 16 days, more wasps will emerge. 8 GREENHOUSE CANADA - September 2026

Application: Application:

New crop, new protection. Reset your biosecurity at every rotation. » Roam Eco Clean: Your Solution for Rapid, Eco-Friendly Cleaning

Active foam cleaner

Outstanding adhesion

Quickly removes plant debris and organic matter

Actively penetrates and dissolves dirt

» Huwa-San TR-50: Complete Disinfection, From Water to Surfaces

Advanced water hygiene

Biofilm removal

No harmful residuals

Superior stability

Our hygiene & biosecurity experts are available to provide guidance. Contact our Agro Solutions Team today for more information & tailor-made advice based on your specific needs. » Tel: +1 (519) 791-6597 (Andrew) or agrosolutions@roamtechnology.com

Horticulture

www.roamtechnology.com

September 2026 - GREENHOUSE CANADA 9

PHOTO: TRACY HUEPPELSHEUSER, BC MINISTRY OF AGRICULTURE

ABOVE: The brown marmorated stink bug (Halyomorpha halys) is the most common species of invasive stink bug found in pepper houses in B.C., having first been detected in the province in 2015.

PHOTO: T. HUEPPELSHEUSER

FIGURE 1. Examples of damage to bell peppers caused by stink bug feeding.

Because eggs are very challenging to find, the main method used for scouting for stink bugs is to look for damage caused by nymphs and adults on pepper fruits. Nymphs and adults that caused the damage will usually be nearby and can be removed by hand. Stink bug distribution in greenhouses tends to be clumped. This is because stink bug eggs are laid in clusters (usually 14–120 eggs each, depending on the species); nymphs that emerge from them will tend to stick nearby the egg laying site while they feed and complete their development. SEASONAL PROGRESSION Adult stink bugs, which probably originate from outdoor populations that are completing their overwintering, start to show up in B.C. pepper houses in May and June. It is likely that these adults come into greenhouses through open roof vents on warm days from May to August. Egg-laying by these adults 10 GREENHOUSE CANADA - September 2026

results in nymphs and eggs in pepper houses, which are observed mostly from July onwards. A mix of life stages of stink bugs are then observed throughout most of the rest of the growing cycle, well into October. Any stink bugs that complete their nymphal development within the greenhouse from August onwards, when daylengths are shorter, will go into reproductive diapause; that is, they will not mate and lay eggs for several months. Some of these diapausing adult stink bugs may persist in concealed areas of pepper houses through the winter clean-out period, complete their reproductive diapause, and then re-infest the crop during the next cycle. We have seen evidence of this in a few commercial greenhouses that start to see issues with stink bugs as early as March and April, well before adults are feeding on plants and laying eggs outdoors. So, pepper houses with a history of stink bug issues should start scouting for stink bugs early in the growing season. SPECIES OF STINK BUGS The current ‘complex’ of stink bugs in B.C. peppers is made up of a mix of native and non-native (invasive) species (Figure 2). The consperse stink bug (Euschistus conspersus) is a native species that was historically the most common species observed in B.C. pepper houses, before the two invasive species arrived. The conchuela stink bug (Chlorochroa ligata) is also a native species that is less common, but can make up a significant proportion of the stink bug complex in pepper greenhouses in years where its outdoor populations are particularly high. The brown marmorated stink bug (Halyomorpha halys) is an invasive species that has been present in B.C. since at least 2015 and is now the most common species of stink bug found in B.C. pepper houses. The brown marmorated stink bug can be distinguished from the similarly brown-coloured consperse stink

Visit ballfloraplant.com for current Terms & Conditions of Sale. ©2026 Ball Horticultural Company 261167600 ™ denotes a trademark of and ® denotes a registered trademark of Ball Horticultural Company in the U.S., unless otherwise noted. They may also be registered in other countries.

THE

GET THE SALES

E arly BLOOMS

NEW Dollarita™ Rose Violet Fuchsia blooms 1-2 weeks earlier than other genetics, so you can be first at retail to get those early sales!

Skip the snooze!

Order NEW Fuchsia on WebTrack®

September 2026 - GREENHOUSE CANADA 11

AUTHORITY IN AGRICULTURAL REFRIGERATION

GREENHOUSE COOLERS www.kooljet.com | (866) 748-7786

FIGURE 2. The adult stage of the four main species of stink bugs currently found in British Columbia pepper houses: (A) Brown marmorated stink bug, Halyomorpha halys; (B) Southern green stink bug, Nezara viridula; (C) Consperse stink bug, Euschistus conspersus; (D) Conchuela stink bug, Chlorochroa ligata. Photos: Tim Haye (CABI Switzerland) and Oregon Department of Agriculture.

bug by the presence of alternating black and white bands on the antennae (Figure 2). The southern green stink bug (Nezara viridula) is the most recently detected invasive stink bug in B.C., having first been found in the Metro Vancouver area in 2019. It is a major pest of greenhouse peppers in Europe and has been detected in at least one B.C. pepper house since 2023, so is a species to watch closely in the coming years. Outdoor populations of this species are restricted to urban areas of Vancouver, possibly because they are only able to persist at northern latitudes on ‘urban heat islands’ (and inside heated greenhouses). It is conceivable that these outdoor populations could act as a source of hitchhiking stink bugs that could make their way into greenhouses. The southern green stink bug can be distinguished from the similarly green-coloured conchuela stink bug by the presence of two or three whitish dots just above the wings in the middle of the body and the lack of a yellow- or orange-coloured margin around the outside of the body (Figure 2). It is not a federally or provincially regulated/quarantine pest. Author’s note: Please feel free to contact me if you think you may have this species in your greenhouse; I’d like to have a better idea of how widespread an issue it is becoming in B.C.

CUSTOMIZED SOLUTIONS

TEMPERATURE | HUMIDITY AIR MOVEMENT

FOR YOUR GROWING ENVIRONMENT

EASY TO INSTALL EASY TO RELOCATE

CHALLENGES WITH MANAGEMENT Stink bugs have proven extremely challenging to manage. One reason for this is that adults migrate into greenhouses over a two- to three-month period and then are long-lived and have an extended egg-laying period that can continue well into September. The fact they feed directly on pepper fruits is also an issue, given the low tolerance for the type of damage they cause – even one or two feeding spots can make fruit unmarketable. In general, stink bugs have high resilience to insecticides, and there do not appear to be any products currently registered for stink bug control that will be effective in controlling them but also preserve biological control of other pests. Growers should, however, check with their provincial entomologist to see if products registered for other pests may have efficacy against some life stages. Unfortunately, there are no currently available commercial biological control organisms available to purchase to help manage stink bugs in North America. The main method for managing stink bugs in B.C. pepper greenhouses is through hand picking. Some growers even pay workers a cash ‘bounty’ to collect stink bugs – a dollar per bug!

12 GREENHOUSE CANADA - September 2026 GH_Kooljet_Dec23_CWM.indd 1

2023-11-06 2:29 PM

Grow More, Worry Less HREZ is designed to actively limit the spread of ToBRFV in the plant and the roots; supporting stable crop performance over time. A long-term solution for optimal protection and performance; built on innovation, evolution, and proven resistance.

Stay ahead of ToBRFV

September 2026 - GREENHOUSE CANADA 13

PHOTO: JJ GOUIN/GETTY

ABOVE Brown marmorated stink bug eggs and first-instar nymphs hatching from eggs. First-instar stink bug nymphs do not feed on plants; they remain on the egg mass to acquire symbiotic microbes from the egg surface.

PHOTO: GABRIEL PACCE/GETTY

ABOVE An invasive southern green stink bug (Nezara viridula) nymph. This is the most recently detected invasive stink bug in B.C., having first been found in the Metro Vancouver area in 2019.

14 GREENHOUSE CANADA - September 2026

FUTURE MANAGEMENT OPTIONS There are commercially available pheromone traps to be used for monitoring (and/or potentially mass collecting) the brown marmorated stink bug outdoors, but our research has shown that they are not effective for any purpose in greenhouse settings. Likewise, there are not any effective pheromone lures available for the other stink bug species. Light traps have also been tested for southern green stink bug monitoring in Europe and in B.C., but with little success. In terms of biological control, egg parasitoid wasps, which specialize on laying their eggs inside stink bug eggs and killing them as a result of their offspring’s development, are the most promising biological control agents. The egg parasitoid Trissolcus basalis is sold for control of southern green stink bug in Europe, but since it is not known to occur in Canada it is not available for purchase in B.C. More encouragingly, there are well-established populations of the main egg parasitoid of brown marmorated stink bug in B.C., the samurai wasp (Trissolcus japonicus - pictured on Page 8). Research is underway in my lab to explore how effective the samurai wasp might be in greenhouse settings, especially when combined with other management strategies such as hand picking adults and nymphs. We have developed efficient rearing techniques for the egg parasitoid and have conducted some preliminary trials under commercial greenhouse conditions in B.C. showing that it is able to locate and parasitize brown marmorated stink bug eggs in greenhouse peppers. Our laboratory experiments have shown that the samurai wasp can also kill eggs of the other three species of stink bugs often found in greenhouse peppers in BC (Figure 2). It is not yet clear, however, whether there is enough of a market for stink bug control to generate interest from commercial biological control companies in mass-producing and selling the samurai wasp in Canada. I am open to ideas from the grower and researcher community as to how we could help make this potential biological control tool available for more widespread testing by growers. Dr. Paul K. Abram is a research scientist at Agriculture and Agri-Food Canada, based out of Agassiz Research and Development Centre in Agassiz, B.C. paul.abram@agr.gc.ca

September 2026 - GREENHOUSE CANADA 15

FRIEND or foe?

Understanding mirid bugs in Canadian greenhouses and the question of Nesi

BY ISABELLA NARDONE, CARLY DEMERS, CARA MCCREARY, ROSELYNE LABBÉ BELOW Nesidiocoris tenuis has a broad host range including tomato, sweet pepper, cucumber, potato and more.

For Canadian greenhouse growers, mirid bugs are a tale of two extremes. On one side are beneficial mirids such as Dicyphus hesperus, valuable biological control agents that help suppress whiteflies, aphids, thrips, and other pests. On the other is Nesidiocoris tenuis (locally called “Nesi” or green bug), an adventive mirid that can provide some pest control benefits but also causes crop damage through its plant-feeding habits. Understanding the differences between these species is increasingly important as Ontario growers encounter more N. tenuis in commercial facilities. WHAT IS A MIRID? Mirids belong to the insect family Miridae, one of the largest families within the order Hemiptera. Many mirids are omnivorous predators, feeding on both plant tissue and insect prey. This feeding strategy, known as omnivory, can be advantageous in greenhouse biological control programs because it allows predators to survive during periods of low pest pressure. However, not all mirids occupy the same place on the omnivory spectrum. At the highly phytophagous end are pest species such as Lygus bugs, which primarily feed on plants and can cause economically damaging levels of crop injury. At the more predacious end are species such as Dicyphus hesperus, a North American mirid commercialized for greenhouse pest control. D. hesperus is valued because it readily attacks

PHOTOS: ISABELLA NARDONE

16 GREENHOUSE CANADA - September 2026

TAKE BACK CONTROL PROVEN BIOINSECTICIDE • Broad-spectrum control of greenhouse pests including mites, aphids, thrips, and whiteflies, with no known risks of resistance. • Excellent rotational compatibility in IPM programs and with biological control agents. • Minimal risk of resistance due to multiple modes of action.

For more information, scan the QR code, or call, Toll-Free: 1-888-236-7378

About Lallemand Plant Care: For over 100 years, Lallemand has been an expert in yeast and bacteria manufacturing. It is now a global leader in the development, production, and marketing of microorganisms for various industries. Using sound science and know-how, Lallemand Plant Care provides effective microbial-based solutions that deliver agronomic, economic, and sustainable value to growers.

September 2026 - GREENHOUSE CANADA 17

whiteflies, aphids, thrips, spider mites and moth eggs while generally causing minimal injury to crops under typical greenhouse conditions. Interest is also growing in other native mirid species such as Dicyphus famelicus and Dicyphus discrepans, which demonstrate predatory capabilities and are currently being evaluated as potential biological control agents in Canada.

ABOVE Dicyphus famelicus is a native mirid species currently under evaluation in Canada to determine its effectiveness as a biological control agent.

Quality, Efficiency, Safety Greefa grading machines are a perfect balance between fruit-friendliness, efficiency and ease of use, with different models available to cover a wide range of fruits and vegetables. We offer integration for complete packing lines, including custom washers, waxers, dryers, dry and wet dumping systems, container handling, and packing equipment. As well as water filtration and purification systems. Available with a large range of measuring systems, including: ● External Quality (iQS) ● Internal Quality (iFA)

● Size ● Weight ● Colour

905.563.8261 | 1.800.263.1287 | info@provideag.ca | www.provideag.ca Beamsville, ON, Canada 18 GREENHOUSE CANADA - September 2026 GH_NM-Bartlett_MarApr23_CSA.indd 1

2023-02-15 8:53 AM

BUILDING A PREDATOR One challenge with omnivorous predators is establishing populations before pest outbreaks occur. To solve this problem, growers often use banker plant systems. For D. hesperus, the most common banker plant is mullein (Verbascum Thapsus). Mullein serves as a refuge and reproductive host, helping predator populations establish and persist even when pest numbers remain low. Banker plants effectively create a “standing army” of predators that can rapidly respond when pests appear. A typical D. hesperus banker plant program involves introducing mullein plants inoculated with D. hesperus at the beginning of the crop cycle before significant pest pressure develops. Supplemental foods such as frozen Ephestia kuehniella eggs are often used to accelerate establishment and reproduction. Research has shown that availability of such supplemental foods can substantially improve survival and population growth of D. hesperus. As greenhouse growers continue to adopt banker systems, questions arise about how native beneficial mirids may interact with unintended occupants such as Nesidiocoris tenuis. MEET THE NEWCOMER Originally recorded from the Madeira Islands, close to mainland Portugal, Nesidiocoris tenuis is now considered nearly cosmopolitan, occurring across Africa, southern Europe, Asia, Australia as well as in North America since at least 1909, where it has been recorded from Florida, Texas and Mexico, with more recent sightings recorded in Ontario. In Mediterranean greenhouse systems it is often intentionally used as a biological control agent against key pests such as tomato leafminer (Tuta absoluta). Interestingly, N. tenuis is unlikely to survive outdoors in cold northern climates like those experienced in Canada.

September 2026 - GREENHOUSE CANADA 19

ABOVE Greenhouse cage studies evaluating interactions between native vs. adventive mirid species at the Harrow Research and Development Centre.

For growers currently dealing with N. Tenuis, an integrated approach is likely to provide the best results.

HOST RANGE Nesidiocoris tenuis has an exceptionally broad host range, having been recorded on plants from numerous botanical families. Hosts include tomato, sweet pepper, cucumber, zucchini, yellow squash, sesame, tobacco, aubergine, and potato. Tomato remains its most commonly associated greenhouse host. Research has also identified strong oviposition preferences for sesame relative to several alternative hosts. At 25°C, N. tenuis develops rapidly, requiring only 21.8 days to complete egg to adult development. This is considerably faster than most Dicyphus species, giving it the potential to build populations quickly in greenhouse environments. WHEN A BIOLOGICAL CONTROL AGENT BECOMES A PEST The challenge with N. tenuis is that its predatory and plant-feeding behaviours are closely linked. The insect increasingly feeds on crop tissue during warmer months even

20 GREENHOUSE CANADA - September 2026

when prey is readily available. On tomatoes, feeding damage appears as characteristic ringed necrotic lesions that lead to stem girdling. These rings typically occur near actively growing tissue and can restrict water and nutrient movement to growing points. Severe infestations may result in aborted flowers, distorted growth, reduced vigour, and yield loss. Both nymphs and adults contribute to plant injury and predation throughout their lifetimes. This dual capacity explains why N. tenuis is considered a valuable biological control agent in some regions and a serious pest in others. PREDATOR VS. PREDATOR As Ontario growers increasingly encounter both N. tenuis and beneficial mirids, attention has turned to evaluating intraguild predation (IGP) as a means of mitigating this species. IGP occurs when natural enemies that share similar prey also feed upon one another or compete

Colour, Consistency, Quality... It’s in the Bag!

Create eye-catching pepper blends with a trio of high performing varieties designed for your value-added line. Together, Schulting RZ, Romboni RZ, and Lavreysen RZ deliver the colour, consistency, and quality designed to help Canadian growers expand and differentiate their offering. From harvest to package, it’s in the bag! For more information: Rijk Zwaan Canada | Sales Manager West | Bradley Breedveld | b.breedveld@rijkzwaan.com RZH Canada LTD | Director of Sales, Max Saad | max@rzhcanada.ca Seminova / Agrocentre Fertibec Inc. | +1 (450) 454 5155 Terralink Hoticulture Inc. | +1 (604) 864 9044 www.rijkzwaan.ca September 2026 - GREENHOUSE CANADA 21

for resources. Such interactions can alter predator populations and influence overall IPM success. Even when direct predation is limited, competition alone can affect establishment, reproduction and population growth. European researchers recently investigated whether three Dicyphus species (D. errans, D. bolivari, and D. cerastii) could suppress N. tenuis populations in greenhouse tomatoes. Their results were striking.

When the Dicyphus species were pre-established approximately five weeks before N. tenuis introduction, population growth of N. tenuis was reduced by more than 90 per cent over an eight-week period. Studies also confirmed reciprocal intraguild predation under certain conditions. These findings suggested that strategic establishment of beneficial mirids might provide growers with a biological means of suppressing problematic N. tenuis populations.

MIRIDS AT A GLANCE: What growers should know

BENEFICIAL VS. PROBLEMATIC MIRIDS • Dicyphus hesperus: Native beneficial predator; thrives on mullein banker plants; attacks whiteflies, aphids, thrips, mites and moth eggs with minimal crop injury. • Dicyphus famelicus: Emerging native predator under evaluation; shows flexible host use and potential to influence N. tenuis distribution. • Nesidiocoris tenuis: Adventive mirid; fast‑developing omnivore; provides some pest suppression but causes tomato stem girdling, aborted flowers and yield loss. KEY TRAITS TO WATCH • Omnivory: Mirids feed on both plants and prey; beneficial when pest pressure is low, risky when plant feeding increases. • Host range: N. tenuis colonizes tomato, pepper, cucumber, squash, sesame and more; tomato remains its primary greenhouse host. • Development speed: At 25°C, N. tenuis completes development in ~22 days: much faster than most Dicyphus species. PRACTICAL MANAGEMENT TIPS • Early monitoring: Use dry yellow sticky cards; scout growing points, suckers, flowers and banker plants. • Sanitation Remove pruned suckers and debris promptly to eliminate egg‑laden plant tissue. • Exclusion Minimum 0.8 × 0.8 mm insect screening needed to block N. tenuis. • Strategic bios — Track interactions between native mirids and N. tenuis, especially around banker plants.

WHAT ARE WE SEEING AT HARROW? Inspired by this work, researchers at Agriculture and Agri-Food Canada’s Harrow Research and Development Centre evaluated interactions between N. tenuis and two North American species: D. hesperus and D. famelicus. Laboratory assays found generally low levels of intraguild predation. The strongest interaction occurred when adult D. famelicus fed on immature D. hesperus. Greenhouse cage studies produced even more interesting results. As expected, D. hesperus strongly preferred mullein banker plants. D. famelicus showed little preference between tomato and mullein. N. tenuis, when alone or combined with D. hesperus, preferred tomato plants. 22 GREENHOUSE CANADA - September 2026 GH_Sollum_Sept26_CSA.indd 1

2026-08-14 8:41 AM

ADVERTORIAL

WSPS Helps Greenhouse Operators Stay Inspection-ready for this Round and the Next As MLITSD inspections continue, use this timely opportunity to review safety practices, strengthen controls and be prepared with support from WSPS.

reenhouse work moves fast, and the margin for error can be small when workers are climbing, lifting and working around powered equipment. In tasks like vine pulling, the risks can be significant. “Contact with moving parts and falls are resulting in critical injuries and even fatalities. So, the severity is quite high,” says Kristin Hoffman, Senior Sector Specialist, Agriculture with WSPS.

High-risk tasks come into focus Inspectors are paying close attention to scissor carts, vine-pulling machines, and vine-shredding machines, familiar tools in greenhouse production, but ones that can create serious hazards when not used as intended. “We’ve heard of some growers take the scissor cart off the heating pipe rails and use it as a platform for maintenance work. This is not what it was intended for,” says Jay Remsik, Health and Safety Consultant with WSPS. “They are not designed to maintain stability when used off the rails,” Kristin adds. “These are narrow carts meant to hold one person. If more than one person is on the platform as it goes up, it could tip over, causing those workers to fall and even get crushed by the equipment.”

for verifying that the workers coming in have completed the required training.

A chance to take stock Preparing for an inspection is a chance to take stock of how work is actually being done, if equipment is being used as intended, and whether the right controls are in place. Kristin says guarding is especially important on vine-pulling and vine-shredding machines. “We know that sometimes guards are removed from vine-pulling and vine-shredding machines because they make it more difficult to position the machine or they impede the flow of waste product,” she says. The solution is to use guards that are specifically designed for the machine. If a machine jams, workers should stop it, lock out the power source, and follow a safe work procedure before clearing the obstruction. “Lockout/tagout is crucial. Ensuring the hazardous energy is safely controlled and locked out will prevent the machine from starting up unexpectedly,” Kristin says.

WSPS support

Vine-pulling and vine-shredding machines bring entanglement and amputation risks. “Basically, vine-pulling machines are rotating shafts and vineshredding machines are exposed augers,” says Jay. “If a worker were to troubleshoot running equipment without locking it out, they could lose a finger, hand, arm, or worse.” He recommends using a dedicated crew with the right training and experience.

For operators looking to stay inspection ready, WSPS can help with workplace walkthroughs, hazard identification, safe work procedures, guarding and lock out best practices and other controls that may need to be strengthened before an inspector arrives. That practical support can help reduce uncertainty and keep operations running smoothly.

Some greenhouse operators contract out tear-out work at the end of the season but responsibility does not end there. Operators are still responsible

Visit WSPS at the Canadian Greenhouse Conference for more information or explore greenhouse safety resources at wsps.ca.

WSPS.CA 1 877 494 WSPS (9777) September 2026 - GREENHOUSE CANADA 23

ABOVE Dicyphus hesperus remains a vital tool for preventative biological control in greenhouses. Emerging research is showing that strategic establishment of beneficial mirids might provide growers with a biological means of suppressing problematic N. tenuis.

However, when paired with D. famelicus, N. tenuis emergence on tomatoes was substantially reduced and shifted toward mullein banker plants. These preliminary findings suggest that while existing D. hesperus banker plant systems may not strongly suppress N. tenuis populations in the short term, D. famelicus may have potential to influence long-term population dynamics and reduce tomato colonization by N. tenuis, with further research on this topic ongoing. REINING NESI IN For growers currently dealing with N. tenuis, an integrated approach is likely to provide the best results. Monitor early and regularly: • Deploy dry yellow sticky cards throughout production areas. Large cards or a high density of small cards will catch more bugs. • Scout growing points, suckers, stems, flowers and banker plants regularly. • Look for characteristic stem lesions and girdling symptoms and developing populations. Good sanitation: • Remove and dispose of pruned suckers and crop debris promptly. Because eggs are inserted directly 24 GREENHOUSE CANADA - September 2026

into plant tissue, removing infested plant material can reduce future populations. Exclusion matters: • Insect screening remains an important tool for reducing movement of pests into greenhouse facilities. For N. tenuis, a minimum mesh size of 0.8 x 0.8 mm is needed to specifically exclude it. Get strategic with bios: • Monitor interactions between naturally occurring and introduced mirids, especially on banker plants which can serve as a host for either species. CHEMICAL OPTIONS Recent efficacy trials have identified several products for N. tenuis suppression and control. Recently, PyGanic (pyrethrin) has received emergency-use registrations in Ontario for greenhouse management programs and may provide growers with an additional tool when economic thresholds are exceeded. As with any insecticide, application timing and compatibility with beneficial insects should be carefully considered. We hope to see more labels including N. tenuis in the future, so stay tuned!

LOOKING AHEAD Mirid bugs are becoming increasingly important players in greenhouse IPM. Native beneficials such as Dicyphus hesperus remain valuable tools for preventative biological control, particularly when supported through mullein banker plant systems. At the same time, the emergence of N. tenuis in Ontario highlights the complex reality of omnivorous predators: the same traits that make them effective natural enemies can also make them damaging pests. The good news is that ongoing Canadian research is starting to uncover how native mirids, banker plant systems, and biological interactions may help growers keep Nesi in check. As understanding grows, greenhouses will be better equipped to harness the benefits of mirids while minimizing their risks. Isabella Nardone is a master’s student of greenhouse entomology or Agriculture and Agri-Food Canada (AAFC); Carly Demers is an environmental sciences doctoral candidate at the University of Guelph; Cara McCreary is the greenhouse vegetable IPM specialist at Ontario Ministry of Agriculture, Food & Agribusiness (OMAFA); and Roselyne Labbé is a research scientist specializing in greenhouse entomology at AAFC. All are based out of the Harrow Research and Development Centre.

September 2026 - GREENHOUSE CANADA 25

Cultivating OpportunitY

@CdnGreenhseConf

CanadianGreenhouseConference.com

N IAGAR A FALL S , O N C ANADA

September 2026 - GREENHOUSE CANADA 27

2026 CANADIAN GREENHOUSE CONFERENCE By Julia vanStaalduinen Marketing & Event Coordinator, Canadian Greenhouse Conference

The Canadian Greenhouse Conference returns in October with another fully booked trade show floor! The 2026 season theme, “Cultivating Opportunity,” celebrates the diversity of horticulture— from fruits and vegetables to ornamental plants, flowers, and trees—highlighting the innovation, sustainability, and opportunities that drive the industry forward. Join us for engaging speaker sessions featuring more than 50 industry experts from across Canada and around the world, sharing forward-looking insights on topics ranging from economics to invasive pests. Explore a dynamic trade show featuring innovative products, advanced technologies, and trusted exhibitors offering the solutions and support you need to grow, improve, and succeed. Don’t miss this opportunity to connect with industry leaders, gain

28 GREENHOUSE CANADA - September 2026

practical knowledge, and discover solutions that can help take your operation to the next level. With more than 15 sessions to choose from, there’s plenty to explore. Visit our website for detailed session descriptions and start planning the agenda that best fits your interests. On October 6th, join the CGC bus tour for a behind-the-scenes look at the diverse greenhouse operations of Essex County. Visit a variety of vegetable, berry, and flower farms, gain valuable insights from industry professionals, and connect with fellow attendees along the way. This unique experience is one you won’t want to miss! Additional details will be announced soon, so be sure to check the CGC website for updates.

Networking is always one of the highlights of the conference, and this year’s two social events—Happy Hour and The Gathering—provide outstanding opportunities to connect with fellow attendees. Generously sponsored by Syngenta Flowers and ICL, Happy Hour offers great food, lively music, and the perfect atmosphere to unwind and recharge after the first day of the show. Then, join us for The Gathering at the beautiful Table Rock House Restaurant, just steps from the breathtaking Niagara Falls. These signature events are the perfect setting to build new relationships, reconnect with colleagues, and enjoy an unforgettable conference experience. Calling all students! The Canadian Greenhouse Conference offers two outstanding opportunities to learn, connect, and showcase your work: the Poster Session and Student Day. The Poster Session provides a platform for sharing the latest research and innovations in Canadian greenhouse horticulture, while the Student Poster Competition highlights emerging talent. Student-led research will be featured online through the CGC website, with select posters displayed during the conference. Student Day returns with a program designed specifically for undergraduate and graduate students, offering valuable opportunities to learn from industry professionals, build connections, and explore careers in the greenhouse sector. Don’t forget to reserve your room at the CGC’s official host hotel, the Marriott

on the Falls. Your stay includes a buffet breakfast—perfect for starting the day, and you might even find yourself dining alongside one of our international speakers. Full details and the booking link are available on our website.A heartfelt thank-you to our conference sponsors! We invite you to discover the exceptional industry partners who go above and beyond to support this event and the broader Canadian growing community. Your dedication helps make the Canadian Greenhouse Conference a cornerstone of our industry calendar, and we are grateful for your continued support.Online registration is open. Take advantage of discount pricing before September 30. Complete conference information is available at www. CanadianGreenhouseConference.com See you at the show!

September 2026 - GREENHOUSE CANADA 29

Cultivating OpportunitY Cultivating OpportunitY

On-site Registration Opens: 8:30 AM | Trade Show Hours: 9:00 AM – 4:00 PM

Trade Show Open 9am-4pm | Morning Sessions 9:30am to 11:00am | Happy Hour 4pm-6pm Trade Show Open 9am-4pm Eff | ective Morning Sessions 9:30am to Plants, 11:00am | Happy Hour 4pm-6pm Mechanization: Little Big Profi ts IPM Bits & Bites, Organic Vegetable Not Every Shoe Fits - Fruit & Vegetable Spores & More Production Effective Mechanization: Little Plants, Big Profi ts Propagation Every Foot IPM Bits & Bites, Organic Vegetable Not Every Shoe Fits - Fruit & Vegetable Spores & More Production Propagation Every Foot

Using Foggers for Crop Protection Greenhouse Using Foggers Louis Dammfor Crop Protection Greenhouse Dramm Corporation

Unplugged Session

Unplugged Session Aron Hoff

for Microbial Products BestMathew Application KrausePractices for Microbial Products

Linwell Gardens Benjamin Alkema Linwell Gardens Thomas Alkema

Do Spore Traps Fit in Greenhouse IPM? Do Spore Traps Fit in Katie Goldenhar Greenhouse IPM?

Linwell Gardens Thomas Alkema Linwell Gardens Paul Vos Foxwood Greenhouses Paul Vos

Meyers Fruit Farms Aron Hoff Louis Damm Dramm Corporation Fruit Farms Benjamin Alkema Best Application Practices Meyers Lallemand Plant Care Mathew Krause Lallemand Plant Care

Ontario Ministry of Agriculture, Katie Goldenhar Foxwood Greenhouses Food and Agribusiness Ontario Ministry of Agriculture, Food and Agribusiness Sponsored by:

Sponsored by: Sponsored by:

Tuesday, October 6th the bus tour offering Tuesday, October 6thCGC the CGC busistour is offering a unique opportunity to tour some of Leamington/ a unique opportunity to tour some of Leamington/ Kingsville’s leading greenhouse operations. Kingsville’s leading greenhouse operations. Valuable insight combined with good fun. Valuable insight combined with good fun. Visit our website for more information. Visit our website for more information. $235 +hst pp – Local Leamington Bus Tour $235 +hst pp – Local Leamington Bus Tour $375 +hst pp – Niagara Overnight Bus Tour $375 +hst pp – Niagara Overnight Bus Tour Advanced purchase only Advanced purchase only

32 GREENHOUSE CANADA - September 2026

Cultivating OpportunitY Cultivating CultivatingOpportunitY OpportunitY On-site Registration Opens: 8:30 AM |Trade Trade Show Hours: 9:00 – 4:00 On-site On-site Registration Registration Opens: Opens: 8:30 8:30 AM AM | |Trade Show Show Hours: Hours: 9:00 9:00 AM AM –AM 4:00 – 4:00 PM PMPM

Trade Show Open 9am-4pm| | Afternoon | Afternoon Afternoon Sessions 2:30pm to 3:30pm Trade Trade Show Show Open Open 9am-4pm 9am-4pm Sessions Sessions 2:30pm 2:30pm toto 3:30pm 3:30pm Aphid Antidotes Aphid Aphid Antidotes Antidotes

New Variety Session New New Variety Variety Session Session

Research Updates Research Research Updates Updates

Berry Innovation Berry Berry Innovation Innovation

Discover thelatest latest innovations Exploring How Abiotic Factors Infl uence Exploring Light Quality Autonomous, Net-zero Discover Discover thethe latest innovations innovations How Abiotic Abiotic Factors Factors Infl Infl uence uence Exploring Light Light Quality Quality Autonomous, Autonomous, Net-zero Net-zero greenhouse crop breeding asas Aphids and Thresholds a Management Tool Greenhouse Strawberry in greenhouse iningreenhouse crop crop breeding breeding Aphids - and -- and Thresholds Thresholds a as Management a Management Tool Tool forforfor Greenhouse Greenhouse Strawberry Strawberry asleading leading vegetable and as as leading vegetable vegetable and and Strawberry Tipburn Production Strawberry Strawberry Tipburn Tipburn Production Production Samantha Willden Samantha Samantha Willden Willden

ornamental breeders showcaseJonah ornamental ornamental breeders breeders showcase showcase Jonah Schaller Youbin Zheng Jonah Schaller Schaller Youbin Youbin Zheng Zheng new varieties and share insightsUniversity new new varieties varieties and and share share insights insights University University of of Guelph Guelph University of Guelph University of of Guelph, Guelph, University of Guelph, into into emerging emerging breeding breeding into emerging breeding Aphid Predators Predators in in CEA Aphid Predators inCEA CEA trends. trends. Learn Learn how how advances advances in in in trends. Learn how advances Strawberries: Strawberries: EffEff ects ects of of LEDs Beyond Beyond PAR: PAR: The The Importance Importance From From Bees Bees to to Breezes: Breezes: Strawberries: Eff ects ofLEDs LEDsperformance, Beyond PAR: The Importance From Bees to Breezes: performance, quality, quality, resilience, resilience, performance, quality, resilience, and Low Low Temperatures Temperatures of of Monitoring Monitoring Natural Natural UVUVUV Transforming Transforming Pollination Pollination and Low Temperatures of Monitoring Natural Transforming Pollination and and market market appeal appeal areare shaping shaping and market appeal are shaping Light Light in in your your Greenhouse Greenhouse Vertical Vertical Farming Farming Light in your Greenhouse in in in Vertical Farming Karli Karli Barton Barton Barton thethe future future of of commercial the future ofcommercial commercial Fadi Fadi Al-Daoud Al-Daoud Habiba Habiba Bougherara Bougherara University University of of Guelph Fadi Al-Daoud Habiba Bougherara greenhouse greenhouse production production and and University of Guelph Guelph greenhouse production and Toronto Metropolitan Metropolitan University University Ontario Ontario Ministry Ministry of of Agriculture, Agriculture, Toronto Metropolitan University creating creating new new opportunities opportunities Ontario Ministry of Agriculture, Toronto creating new opportunities Food Food & Agribusiness & Agribusiness for for growers. growers. Food & Agribusiness for growers. Aphids Aphids Out Out Aphids Out Cornell University Cornell University University

of of of Control Control Control

Mariska Mariska Beekman Beekman Mariska Beekman

Aphid Aphid Antidotes: Antidotes: Balancing Balancing Aphid Antidotes: Balancing Insecticide Insecticide Effi Effi cacy cacy and and Insecticide Effi cacy and Biological Biological Control Control in Biological Controlin in Greenhouse Greenhouse Peppers Peppers Greenhouse Peppers

Azimove Azimove Sulthana Sulthana Azimove Sulthana Agriculture Agriculture & Agri-Food & Agri-Food Canada/ Canada/ Agriculture &Windsor Agri-Food Canada/ University University of of Windsor University of Windsor

Year-Round Year-Round Blueberry, Blueberry, Year-Round Blueberry, Raspberry, Raspberry, and and Blackberry Blackberry Research Research Update Update ononon Raspberry, and Blackberry Research Update Production Production in in Canada Canada Biocontrol Biocontrol of of Tomato Tomato Brown Brown Production in Canada Biocontrol of Tomato Brown Eric Eric Gerbrandt Gerbrandt Rugose Rugose Fruit Fruit Virus Virus Eric Gerbrandt Rugose Fruit Virus BeriTech BeriTech Inc.Inc. Inc. Aiming Aiming Wang Wang BeriTech Aiming Wang Agriculture Agriculture & Agri-Food & Agri-Food Canada Canada Agriculture & Agri-Food Canada

Producing Producing Disease-Free Disease-Free Producing Disease-Free Strawberry Strawberry Transplants Transplants Built Built forfor the the Greenhouse: Greenhouse: Strawberry Transplants Built for the Greenhouse: Vincent Vincent Hall Hall The The Next Next Wave Wave of of Canadian Canadian Vincent HallInc.Inc. The Next Wave of Canadian Pépinière Pépinière Cultivar Cultivar Strawberries Strawberries Pépinière Cultivar Inc. Strawberries Jason Jason Lanoue Lanoue Jason & Lanoue Agriculture Agriculture Agri-Food & Agri-Food Canada Canada Agriculture & Agri-Food Canada

Update Update onon the the Native Native Update Breeding onBreeding the Native Ornamental Ornamental Ornamental Breeding Program Program Dr.Dr. AlProgram Al Sulivan Sulivan Dr. Alof Sulivan University University of Guelph Guelph University of Guelph

Investigating Investigating Wood Wood Fiber Fiber asas a a Investigating Wood Fiber as a Sustainable Sustainable Substrate Substrate Option Option forfor use use in in Greenhouse Greenhouse Berry Berry Sustainable Substrate Option Production Production for use in Greenhouse Berry Production Carly Carly Lacy Lacy Walker Walker Ind. Ind. Carly Lacy Walker Ind.

Titles Titles & speakers & speakers subject subject to change. to change. Visit Visit CanadianGreenhouseConference.com CanadianGreenhouseConference.com forfor up-to-date up-to-date information. information.

Titles & speakers subject to change. Visit CanadianGreenhouseConference.com for up-to-date information.

Highlighting Highlighting current current research research onon greenhouse greenhouse

Explore Explore greenhouse greenhouse growing growing atat Student Student Day Day —— aa

Highlighting current research on greenhouse floriculture, floriculture, fruit, fruit, vegetables, vegetables, and and alternative alternative crops crops in in Canada. Canada. This This includes includes regular regular and and fl oriculture, fruit, vegetables, and alternative student student competition competition posters. posters. crops in Canada. This includes regular and More More details details online. online. posters. student competition More details online.

Explore greenhouse growing at Student Day — a half-day half-day event event designed designed to to launch launch your your horticulture horticulture career. career. Connect Connect with with industry industry professionals, professionals, discover half-day event designed to launch your discover horticulture career career opportunities, opportunities, and and take take your your first first steps steps toward toward career. Connect with industry professionals, discover a future a future in in the the sector. sector. and take your first steps toward career opportunities, More More details details online. online. a future in the sector. More details online. September 2026 - GREENHOUSE CANADA 33

Here’s a sneak peek at some of this year’s speakers DIANE BLAZEK

All-America Selections From her Missouri family farm roots to the colourful green spaces of her suburban lot, Diane Blazek’s passion for horticulture has been lifelong. As current Executive Director of National Garden Bureau (NGB) and All-America Selections (AAS), a position held since 2010, she has led both organizations through growth, modernization and expanded outreach to home gardeners.

LUCAS CHAPDELAINE Whole Leaf

Lucas Chapdelaine is Assistant Director of Growing and Operations at Whole Leaf, one of North America’s most advanced greenhouse lettuce operations, located near Coaldale, Alberta. His hands-on expertise spans pest control, climate, and irrigation, and he leads the harvest team that packs more than 60,000 heads daily.

CELINA GÓMEZ

Purdue University Celina Gómez is an Associate Professor at Purdue University leading a crosscommodity research program in controlledenvironment agriculture (CEA). Her expertise includes plant lighting, propagation, hydroponic production, and citizen science. She integrates research, teaching, and Extension to improve productivity and quality of specialty crops in CEA.

34 GREENHOUSE CANADA - September 2026

PETER HALL

Econosphere Inc. Peter hall is CEO of Econosphere inc., offering strategic advice to Canadian corporations, business associations and policymakers. He is the former chief economist of Export Development Canada (EDC) and also directed the economic forecasting group at the Conference Board of Canada.

ERI HAYASHI

Japan Plant Factory Association Serving as president of Japan Plant Factory Association, a nonprofit organization devoted to academic and business advancements in plant factory/CEA, Eri has a keen interest in plant factories’ technological advances, including phenotyping. She received a Ph.D. from Chiba University in Japan and she is an Associate Member of the Science Council of Japan.

their evidence-based research aims to reshape CE agricultural practices for a more sustainable future. Dr. Hernández has led a controlled environment propagation research program for the past 15 years, making significant contributions to the development of environmental protocols and technologies aimed at improving the propagation of horticultural crops.

GABRIËL VAN DER KRUIJK LetsGrow

Gabriël van der Kruijk combines hands-on tech expertise with deep horticulture experience. As Managing Director of LetsGrow.com, he cuts through AI hype with practical, customerfocused insights. Drawing on digital transformations at Rijk Zwaan and Koppert, he helps audiences and workshop participants turn technology into concrete business impact and solutions.

SAMANTHA WILLDEN RICARDO HERNÁNDEZ

North Carolina State University Dr. Ricardo Hernández (Co-I) is an Associate Professor at North Carolina State University (NCSU), focused on controlled environment research, specializing in optimizing environments to maximize plant responses. As the Director of the CEA-Coalition at NCSU, he heads a multidisciplinary research group. Collaborating with scientists, engineers, and industry partners,

Cornell University Samantha is an Assistant Professor of Entomology at Cornell University with a research/extension appointment in Controlled Environment Agriculture (CEA). She has a strong background in community ecology and biocontrol. Her current program investigates how abiotic and biotic factors shape insect communities in CEA to develop more pest-resilient cropping systems.

Cultivating OpportunitY

September 2026 - GREENHOUSE CANADA 35

@CdnGreenhseConf

CanadianGreenhouseConference.com

STEAM cleaned

PHOTOS: KARLI BARTON

Thermotherapy proves an IPM boon for greenhouse strawberries BY KARLI BARTON

Cyclamen mite (Phytonemus pallidus) is one of the most difficult pests to manage in greenhouse strawberry production. Carefully hidden in folded leaves and crowns of their host plants, cyclamen mites are microscopic and often go unnoticed until plants begin showing distorted growth, reduced vigour, and lower yields. Because they feed on the youngest developing tissues, early symptoms may be mistaken for calcium deficiency, resulting in delayed treatments when populations have already increased (Figure 1, on page 39). Once established, cyclamen mites are very difficult to control because

they are protected from contact pesticides and might be challenging for predatory mites to reach. LIMITED OPTIONS As chemical control options are limited, new methods are needed to keep cyclamen mites out of production systems while supporting biological control programs. One promising approach is steam treatment of transplants before planting. Steam treatment (sometimes called “plant thermotherapy”) has already shown promise for eliminating pests and diseases from dormant strawberry plants. In addition to cyclamen mite,

ABOVE Experimental greenhouse trial evaluating integrated cyclamen mite management. Strawberry plants were maintained in individual mesh cages to prevent movement of mites and predatory mites between treatments while allowing researchers to compare steam treatment, biological control, and miticide programs under greenhouse conditions. 36 GREENHOUSE CANADA - September 2026

September 2026 - GREENHOUSE CANADA 37

previous work has demonstrated good control of powdery mildew, botrytis, angular leaf spot, and anthracnose. However, there is little information on how steam-treated plants perform in greenhouse production and when biological control programs are used. To help answer this question, we evaluated whether steam-treated strawberry transplants could be successfully integrated with predatory mites or conventional miticides in greenhouse strawberry production to effectively control cyclamen mite.

Hidden in folded leaves and crowns, cyclamen mites are microscopic and often go unnoticed until plants begin showing distorted growth, reduced vigour, and lower yields.

EXPERIMENTAL APPROACH Dormant strawberry transplants (‘Albion’) were artificially infested with cyclamen mites before receiving either steam treatment or not. Steam treatments were applied in a modified growth chamber at AAFC’s Vineland Research and Development Centre. Plants were exposed to steam under carefully controlled temperature and airflow conditions to ensure uniform heating while minimizing plant stress. The steam protocol was 37°C for one hour to acclimatize the plants, a one-hour resting period, followed by 44°C for four hours. Following planting, each group received either no additional treatment, predatory mites Amblyseius cucumeris or Amblydromalus limonicus, or the insecticide Avid (abamectin). We monitored plants weekly for eight weeks, keeping track of cyclamen mite populations and plant damage over time. At the end of the trial, plants were weighed to determine whether biomass was affected by the different treatments.

38 GREENHOUSE CANADA - September 2026

EXCEPTIONAL CONTROL The difference between steam-treated and untreated plants was apparent almost immediately. Across all post-treatment programs, there were very few cyclamen mites on steam-treated plants throughout the eightweek trial. In contrast, cyclamen mite populations increased steadily in untreated plants regardless of whether biological control or chemical treatments were applied. Measurements taken at the end of the trials showed that steam-treated plants produced approximately 22 per cent more biomass than the untreated plants, while no differences in biomass were detected among the group subjected to postplanting treatments. These findings clearly show that beginning production with clean planting material was far more effective than trying to manage infestation after planting. An unexpected finding throughout the course of the trial was the potential for disease suppression. Eleven weeks after steam treatment, and without any fungicide applications,

FIGURE 1 Cyclamen mite damage can closely resemble calcium deficiency. Cyclamen mite feeding (left images) causes puckered, distorted young leaves that are often mistaken for calcium deficiency (right images), making early detection and diagnosis challenging.

Biological solutions and expert guidance for modern crop production. Biobest helps growers build resilient cropping systems by working with nature - combining biological control, pollination, and integrated pest management (IPM) expertise to support sustainable crop outcomes.

Expert solutions for resilient, productive crops • Pollination • Biological Control • Monitoring & Scouting • High-tech IPM Solutions

ABOVE Researchers applied steam treatments to dormant strawberry transplants that were artificially infected with mites. Plants were then monitored for eight weeks.

Call your local representative today.

Distributed by

GH_Plant Products_May26_CSA.indd 1

September 2026 - GREENHOUSE CANADA 39 2026-04-08 12:49 PM

powdery mildew incidence was three per cent on steam-treated plants compared with 59 per cent on untreated plants. For growers, these results suggest that investing in steam treatment technology for treating transplants before planting can provide benefits throughout the production cycle. BIOLOGICAL CONTROL STILL PLAYS KEY ROLE Steam treatment was clearly the most effective strategy, but not every grower has

access to steam treatment equipment or steam-treated transplants. Among plants that did not receive steam treatment, the predatory mite Amblyseius cucumeris consistently provided the greatest suppression of cyclamen mites. Plants receiving A. cucumeris generally maintained lower mite populations and showed less plant damage than untreated controls. A. limonicus also reduced damage, although results were less consistent

SPECIALIZING IN LASER GRADING FOR: Greenhouses • Cultivation Floors • Sports Projects Parking Lots • Driveways

compared to A. cucumeris. One application of the miticide Avid provided suppression but did not outperform A. cucumeris under the conditions of this study. While none of the post-planting treatments fully compensated for starting with infested plants, the results demonstrate that biological control remains an important component of an integrated management program, particularly when steam treatment is not available. BUILDING A STRONGER IPM PROGRAM The biggest lesson from this work was that preventing cyclamen mites from entering the greenhouse on infested transplants is much easier than trying to eliminate them later. Steam treatment dramatically reduced the number of mites entering production while improving plant growth and reducing disease pressure. Biological control can then be used, if necessary, to help maintain those low populations throughout the crop. As greenhouse strawberry production continues to expand across Canada, preventative approaches such as steam treatment may become an increasingly valuable tool for reducing pesticide use while supporting effective biological control programs.

Steam treatment was clearly the most effective strategy, but not every grower has access to steam treatment equipment or steamtreated transplants.

Although additional commercial-scale research is still needed, particularly for assessing any yield differences, these results suggest that combining clean planting material with biological control could become an important component of sustainable greenhouse strawberry production. info@degrootlasergrading.com • 905-933-7810 • degrootlasergrading.com

40 GREENHOUSE CANADA - September 2026 GHC_GEORGEDEGROOT_APR26_JLR.indd 1

2026-04-15 1:02 PM

FUNDING AND ACKNOWLEDGMENTS This research is an Agri-Science Project under the Sustainable Agriculture Partnership (SCAP-ASP-085 Berry Growers ON – Activity #2: Managing Pests on Greenhouse and Vertically Farmed Strawberries). Thank you to Berry Growers of Ontario and Koppert Canada for funding this research. Thank you to Dr. Justin Renkema and Sudhakar Pandurangan (AAFC London Research and Development Centre) for their expertise and support with the steam treatment component of the project. PHOTO: DUTCHSCENERY/GETTY

Karli Barton is an MSc student in the School of Environmental Sciences at the University of Guelph, where she is co-supervised by Dr. Rebecca Hallett and Dr. Roselyne Labbé. Her research is based at Agriculture and Agri-Food Canada’s Harrow Research and Development Centre (HRDC) and focuses on developing integrated pest management strategies for greenhouse strawberry production. She also collaborates with Dr. Justin Renkema at AAFC’s London Research and Development Centre on research related to steam treatment of strawberry transplants.

ABOVE Greenhouse strawberry production is rapidly expanding across Canada and preventatitive pest and disease management approaches, like steam treatments, may be an increasingly valuable tool to reduce dependence on chemical controls.



   

Now you can buy directly from the manufacturer at lower price than before

  





  



A Canadian manufacturer for agricultural, horticultural, and forestry equipment of 30 years. We’re dedicated to improving productivity and efficiency in the greenhouse. Visit our web site to discover the soil fillers, bale breakers, conveyors, and the new seeding line we offer.

Visit our website:

www.sbee.ca

September 2026 - GREENHOUSE CANADA 41 GH_NIC_Sept26_CSA.indd 1

GH_MachineriesSB_JUNEJULY25_BAS.indd 1 2026-08-12 3:12 PM

2025-05-26 9:39 AM

PHOTOS: MOHYUDDIN MIRZA, VIKRANT DHAWAN, JASHANDEEP SINGH

The disease equation How shifts in temperature, moisture and oxygen create a perfect storm for wilt‑causing pathogens BY VIKRANT DHAWAN, JASHANDEEP SINGH AND MOHYUDDIN MIRZA

A wilted plant is often the first visible warning that something has gone wrong inside a greenhouse. Leaves lose their firmness, growth begins to slow, and plants may gradually, or sometimes rapidly, decline. Yet wilt itself is not a disease; it is a symptom that can develop when water movement through the plant is disrupted by root damage, vascular infection, environmental stress, or a combination of these factors. What makes wilt particularly challenging in greenhouse production is that the environment can influence how strongly a disease develops. Temperature, humidity, moisture, irrigation practices, air movement, and plant stress interact with the host and pathogen to create the conditions under which disease can establish and spread.

Understanding this interaction is especially important when producing high-value crops such as cannabis, tomato, and cucumber. DISEASE TRIANGLE Plant disease is commonly explained through the disease triangle: host, pathogen, and environment. A susceptible crop and a pathogen may be present without causing significant disease until environmental conditions become favourable. The more favourable those conditions become, the greater the potential for disease development and severity. Greenhouse production provides an advantage because many environmental variables can be monitored and influenced. However, rapid changes in temperature, prolonged high humidity,

ABOVE An example of mature cannabis plants early wilting symptoms which was diagnosed to be due to very high relative humidity, over 90 per cent and a Vapour Pressure Deficit of less than a gram/m³ of air. Transpiration from leaves was reduced and all metabolic activities were negatively affected. 42 GREENHOUSE CANADA - September 2026

RIGHT Recently planted cucumber seedlings showing wilt due to the fungus Pythium and also missing couple of fertigation.

condensation, excessive moisture, poor air movement, or stressed plants can shift the balance in favour of disease. This is why environmental records can be just as valuable as visual symptoms when investigating a wilt problem. WILT BELOW THE CANOPY Cannabis can be affected by several soil- and substrate-associated pathogens, including species of Fusarium and Pythium. Fusarium species have been documented as causes of root rot, crown rot, damping-off, and wilt in cannabis. Symptoms may include chlorosis, stunting, root or crown discoloration, and, in more advanced cases, wilting. Environmental conditions can influence how quickly these problems progress. High humidity can encourage fungal growth, while excessive moisture around roots can create favourable conditions for certain root pathogens. In a commercial greenhouse, disease management therefore begins with

preventing favourable conditions from developing and maintaining consistent sanitation and crop monitoring. When wilt appears, growers should examine the roots, crown, and lower stem rather than assuming the plant simply requires more water. The distribution of affected plants can also provide valuable

information: isolated plants may suggest a localized problem, while a pattern following irrigation or water movement may point toward a different source. TOMATO WILT Tomato provides a clear example of how environmental conditions can influence

Among the Most Energy-Eﬀicient Greenhouse Fans worldwide

Multifan Greenhouse Fan

• Extremely eﬀicient • Low-noise level • Easy installation

Multifan V-FloFan

• Corrosion-resistant materials • IP-55 rated • 3-year warranty

Proudly Distributed in Canada by: www.exaconinc.ca sales@exacon.ca

September 2026 - GREENHOUSE CANADA 43 GH_Exacon_MarApr26_CSA.indd 1

2026-02-11 GH_BenBerg_FlatFiller_Jan25_CWM.indd 11:46 AM 1

2025-01-30 3:38 PM

LEFT A view of the cross-section of a wilting tomato plant stem, about 12 inches from the base.

works alongside sanitation, resistant varieties where available, and appropriate disease monitoring.

wilt disease. Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici, is favoured by warm conditions. Symptoms can include yellowing, wilting, and discoloration of the plant’s water-conducting tissues. Verticillium wilt can produce similar symptoms but is generally associated with cooler conditions. Because the symptoms overlap, temperature history can provide

an important clue, but it should not replace proper diagnosis. Greenhouse tomatoes also demonstrate the importance of humidity management. Dense canopies, limited airflow, condensation, and prolonged periods of high relative humidity can increase pressure from several diseases. Good environmental management therefore

CUCUMBER: SPEED MATTERS Cucumber can experience wilt associated with both soil- or substrate-borne pathogens and bacterial diseases. They are very sensitive to oxygen dynamics in the root zone and when dissolve oxygen drops below 4 mg/L then damping off molds like Pythium spp. attack roots and wilting occur. Then Fusarium and verticillium and Gummy Stem Blight can all attack plant. Wilt causing fungi generally attack when plant is fully loaded with fruit and can cause a significant economic loss. This illustrates why greenhouse disease management cannot focus only on humidity and irrigation. Pest management, sanitation, environmental monitoring, and early scouting all form part of the same disease-prevention strategy.

New Construction & Retrofit

SOLUTIONS GREENHOUSE STRUCTURE CURTAIN SYSTEMS HEATING & COOLING

DESIGN + BUILD+ SERVICE Family owned and operated since 1978.

Office: 905.984.8711 ›› info@langendoenmechanical.com ›› www.langendoenmechanical.com 44 GREENHOUSE CANADA - September 2026 GH_Langendoen_Jan25_CSA.indd 1

2024-12-04 3:52 PM

RIGHT Tomato stems producing adventitious roots is an indication of high relative humidity and poor air movement.

READ THE ROOM When wilt appears, the plant itself is only part of the story. Growers should ask what changed before symptoms appeared. Was there an unusual temperature event? Did humidity remain elevated overnight? Was condensation present? Did irrigation patterns change? Were affected plants concentrated in one section of the greenhouse? Has airflow changed as the canopy became denser? The answers can help distinguish environmental stress from an infectious disease and can also provide clues about how a pathogen may be developing. Examining roots, crowns, and vascular tissues can provide additional information. Where symptoms are unclear or multiple causes are possible, laboratory diagnosis is valuable because treating the wrong problem can delay corrective action while disease continues to develop. CONTINUED ON PAGE 56

Printing & beyond ...Here & there ! www.horticolor.net

Cam Duggan Business Development Manager

Cell: 1 (226) 668-1890 camduggan@maxpkgsolutions.com 1025 - 8th Street East, Owen Sound, On, Canada N4K 1M5

GH_MAXSolutions_Sept26_CSA.indd 1

September 2026 - GREENHOUSE CANADA 45 2026-07-15 3:30 PM

TSUNAMI of uncertainty

Geopolitical shocks, rising energy costs and fragile supply chains reshape economics of Canadian floriculture

BY BY J. LYNN FRASER BELOW The U.S. is the biggest importer of Canadian floriculture products.

According to Statistics Canada, the cut-flower industry’s highest operating expenses in 2024 were plant materials, annual payroll, natural gas, electricity, and heating oil. In 2026, geopolitics has become another operating pressure. The ongoing unrest in the Middle East is expected to have serious global consequences affecting billions of people. Its reach and effects could be felt for years to come. Expected impacts include: • economic instability, reduced GDP, recession, and lower investment; • rising unemployment, weaker consumer spending, and declining consumer confidence; • currency volatility and higher fossil fuel costs; • higher consumer-goods prices and shortages of key goods. The International Energy Agency (IEA), in its Sheltering From Oil Shocks report published early this year, stated its concern about impacts on the global economy. The Bank of Canada (BOC), while keeping interest rates at 2.25 per cent, stated that increasing oil and gas prices will cause a surge in global inflation. For Canadian growers, these pressures land directly on the balance sheet in higher fuel and electricity costs increase heating expenses, transportation costs and landed input prices. As a result, current conditions may encourage some growers to choose alternative energy sources such

PHOTOS: SUPPLIED

46 GREENHOUSE CANADA - September 2026

SHOCK ABSORBERS Tariffs are only one part of the pressure facing growers and they underscore the broader need for stronger risk‑management strategies. Aliya Daya, a senior client executive for Acera Insurance, offers advice on risk mitigation:

A game-changing innovation in growing media!

“For small/medium growers, access to plugs/ bulbs is an issue.”

Reduced Freight Costs & Simpliﬁed Logistics

The gel powder formulation replaces bulky substrate shipments, requiring signiﬁcantly less transport volume and storage, lowering logistics costs and reducing supply chain risk.

GH_Jiffy_Sept26_CSA.indd 1

Biodegradable & Sustainable

Made from sustainable, plant-based materials, supporting environmentally responsible growing practices.

JIFFY PRODUCTS OF AMERICA INC. Toll-free: 1-800-323-1047 (North America only) E-mail: prosales@jiffygroup.com

www.jiffygroup.com

Produced from premium, food-safe materials, delivering a clean and pathogen-free growing media.

JIFFY PRODUCTS INTERNATIONAL BV Tel.: +31 78 20 62 100 E-mail: sales@jiffygroup.com

Pathogen-Free & Food-Safe

Full visibility and control over substrate preparation directly at the farm, ensuring consistency, ﬂexibility, and operational independence.

tio

On-Farm Substrate Production

Sca

Geopolitical conflict also has an impact on the pricing of nitrogen fertilizer, transportation, logistics, landed costs, and input and fuel costs for Canadian growers. Growers also face challenges due to energy prices, carbon pricing, attracting foreign workers, shifting investment, and a reliance on exports. Tariff threats and unpredictable White House policies are significant challenges, in fact one of the most significant facing Canada’s floriculture producers as the main importer of Canadian cut flowers is the U.S. (GOC). Michel Benoit, United Flower Growers Co-op Association, describes tariffs “as an incredibly destructive force in the supply and for consumers. They are putting people on edge.”

A revolutionary gel-based substrate composed of water and plant-based materials.

CHALLENGES In 2024, Canada’s production of cut flowers was valued at $230.5 million (The Daily, GOC) and there are a number of challenges currently facing the industry. “For small/medium growers’ access to plugs/bulbs is an issue,” said Janis Harris, Canadian Regional Director, Association of Specialty Cut Flower Growers. “The plug plant infrastructure for cut-flower production is not very big in Canada. Many must still buy plug plants that are imported from the U.S. This causes higher costs, extra phytosanitary inspection and risk delays that decrease the quality of the plugs.” The “costs of shipping within Canada is also a big issue. [As are] sending plants, bulbs, seeds,” notes Harris, who is also co-owner of Harris Flower Farm in St. Thomas, ON. She points out the importance of “access to grant funding to increase growing potential, especially for small/medium growers and outdoor cutflower producers.”

RIGHT Novel approaches to things like crops and means of sales and delivery could help growers pivot in a pinch.

as biomass, biofuels, geothermal, solar/ photovoltaic panels, electricity, and heat pumps; technologies that can help buffer operations against future volatility.

ke e

p up with t

his

September 2026 - GREENHOUSE CANADA 47 2026-07-21 9:48 AM

First, she suggests businesses perform a risk analysis: Use current data and expert analysis to assess crisis scenarios and responses. Second, evaluate supply chains. Do not rely on one region for significant supplies and where possible, use suppliers who are close by and in stable regions. Third, assess suppliers and assess risks involved in using them. Use many suppliers and employ long- and shortterm contracts. Finally, have in place diverse insurance options.

Responses to political risks by Canadian business, says Patrick Rengger, a senior advisor at HUB International, typically occur after a geopolitical event has started — when it may be too late (Cdn Bus. Mag, 2025). Rengger suggests that a business’s first step should be to set up decisionmaking plan. He notes that insurance can be customized for problems with contracts, currency, trade credit, terrorism, supply chains, marine and cargo, environmental liability and climate risk. In a speech at the 2026 World

ABOVE Recent geopolitical uncertainty has resulted in higher fuel and electricity costs, transportation and landed input prices for Canada’s flower growers.

Integrated solutions to support healthier greenhouse crops Plant Products supports greenhouse growers across North America with a broad portfolio of crop inputs designed to meet real world production challenges. Integrated solutions, backed by expert support: • Integrated pest management (IPM) solutions designed to ﬁt your production program. • Crop inputs that support consistent plant health and performance. • Knowledgeable technical and IPM representatives providing practical, on crop guidance.

Talk to your Plant Products representative to learn more. The Plant Products logo is a registered trademark of Plant Products. Other trademarks are properties of their respective owners. © 2026 Plant Products

48 GREENHOUSE CANADA - September 2026 GH_PlantProducts_JuneJuly26_CSA.indd 1

PlantProducts.com

2026-05-20 7:55 AM

Economic Forum in Davos, Switzerland, Prime Minister Mark Carney spoke on how the traditional world order is ‘not coming back.’ He explained how Canada is adapting, stressing the concept of variable geometry, a flexible framework that facilitates development and co‑operation among members within a broader collective. It enables members to work together in a variety of areas and at different speeds based on issues as they develop. The variable geometry approach can be used by growers to navigate uncertainty building collaborations across different business sectors. ‘BUY CANADIAN’ In the past, Colombia, Ecuador and Kenya were able to supply cut flowers at lower retail prices than Canadian growers. Their production costs were significantly reduced by inexpensive labour, abundant water availability, low energy use and minimal environmental regulation. Canadians like the price points but are unaware of the hidden costs. In Ecuador, for example, growers use fungicides, pesticide and insecticides, which have environmental costs and negatively affect workers’ health. Similar concerns have been raised about Colombia and Kenya. A campaign aimed at educating Canadians about the hidden costs of these imports, giving consumers an opportunity to make an informed choice. Prominent labelling stating ‘Grown in Canada by Canadians for Canadians’ could be effective.

LEFT Canada’s flower growers’ reputation for quality gives the sector an edge in an uncertain moment, experts say.

Selling Canadian values and products to Canadians is a viable marketing approach. Canadians responded to tariffs and White House rhetoric by taking 10 million fewer trips to the U.S. and made more trips within Canada in 2025 (BOC 2026). Canadians also choose Canadian groceries over U.S. ones. During the 2019 holiday season, Roots ran its ‘Nice Together’ campaign celebrating niceness and community. The ‘Get Cracking’ campaign of Egg Farmers of Ontario informs Ontarians about eggs while allowing customers to get-to-know

egg farmers. These approaches can work for cut-flower growers. “I always hear from farmer florists and florists that buy flowers that Canadian Snapdragons and gerbera daisies are the BEST. Also, Canadian lisianthus,” says Harris. Her advice: “Continue to grow GREAT quality. That is what Canadians are known for.” BROADEN THE CELEBRATION Dr. David Wees, associate director of the Farm Management and Technology program at McGill, suggests growers could offer

novel flowers or consider new delivery and sales methods, including: selling online, subscription services, co-operatives, and direct delivery. New customers can be found in special interest and cultural groups. Consider customized bouquets for: Canada Day, Eid, Diwali, Thanksgiving, and Caribbean Carnival. In Chinese culture it is customary to send flowers to businesses on their opening day. Orchids, peonies, sunflowers, anthuriums, red roses, gerberas are sent to show support and encourage guanxi (professional relationships). Corporate Canada, another ‘cultural’ group, has numerous occasions to celebrate with cut flowers. “We are in the midst of a rupture,” Carney has said, “not a transition.” The variable geometry for cut flower growers means developing flexible strategies and collaborations needed to mitigate geopolitical uncertainty.

26_008020_Greenhouse_Canada_SEP_CN Mod: June 26, 2026 4:03 PM Print: 07/23/26 page 1 v2.5

π SPEC-TACULAR SELECTION SAFETY GLASSES IN STOCK

ORDER BY 6 PM FOR SAME DAY SHIPPING

GH_Uline_September26_CSA.indd 1

1-800-295-5510

uline.ca

September 2026 - GREENHOUSE CANADA 49 2026-07-24 12:34 PM

GROWING MORE than flowers

She Grows: Janis Harris turned a few gladiolus into a farm, a following, and push to get Canadian flower growers seen BY AMY KOUNIAKIS BELOW Janis Harris on her farm, the Harris Flower Farm, in St. Thomas, ON.

For nearly two decades, Janis Harris has been building something bigger than a flower farm. Today, Harris Flower Farm in St. Thomas, Ontario, is an eight‑acre operation producing thousands of stems across heated and unheated greenhouses and full field production. But the real story, the one that earned Harris a place among the inaugural She Grows honourees, is how she has helped build space, confidence, and representation for Canadian flower farmers across the industry. Harris didn’t set out to become a farmer. She grew up on an organic vegetable operation, “organic before organic was cool,” she jokingly recalls her parents saying, but as a teenager, she says she wanted nothing to do with agriculture and she set off to make her own way in the world. She trained as an optician and worked in clinics and optical shops for years. Farming, she thought, was behind her. BACK TO ROOTS But life has a way of circling back. When she met her future husband, who came from a beef operation, she felt the pull to grow something again. Her

PHOTOS: JANIS HARRIS

50 GREENHOUSE CANADA - September 2026

mother suggested gladiolus. Harris planted 3,000 bulbs that first year. This was done after work, on borrowed land, with her husband helping her pick and bunch stems for the Horton Market in St, Thomas. “It just kind of grew from that every year,” she says. It grew into a business, then a calling, then a community. The early years were a patchwork of rented plots, borrowed equipment, and experimentation. Harris planted wherever someone would let her work up a bit of ground. She learned through trial, error, and the humbling unpredictability of field‑grown flowers, a theme she returns to often.

“It’s really just a full season of flowers,” she said. Harris’s leadership extends far beyond her farm. She has become one of the most visible advocates for Canadian specialty cut‑flower growers, a role she stepped into almost accidentally. Her first Association of Specialty Cut Flower Growers (ASCFG) event was a family road trip to Ohio. “I was like, this is really cool; talking to other people who want to talk about flowers all day,” she remembers fondly.

ADVOCACY Once involved, though, she quickly started noticing gaps in Canadian representation among ASCFG. Events were scheduled on Canadian Thanksgiving, resources were largely U.S.‑centric. and suppliers and growing conditions weren’t comparable. She spoke up repeatedly until the association created a dedicated Canadian director role. Harris became the first to hold the position. “I kind of made enough noise

Harris didn’t set out to become a farmer. She grew up on an organic vegetable operation, “organic before organic was cool.”

In 2011, she and her husband bought her grandparents’ former dairy and cash‑crop farm and converted the entire property to flowers. Greenhouses went up and crop plans expanded. And as demand grew, so did the team. Today, Harris manages a seasonal crew of about seven, most of whom return year after year; a seeming rarity in seasonal agriculture. “This is one of the first years we have only one new person on our team,” she says. “It’s really great for seasonal work.” FULL SEASON OF FLOWERS Her days shift constantly: picking, planting, fulfilling online orders, assembling grocery‑store bouquets, managing wholesale accounts. “Every day changes and we have to pivot all the time,” she says, a word she grudgingly uses but admits is accurate. The farm now produces a full season of flowers: pussy willows in February, greenhouse tulips, field daffodils, ranunculus, anemone, lilacs, zinnias, marigolds, sunflowers, lilies, celosia, lisianthus, dahlias and, more recently, roses.

Your local partner for greenhouse projects Greenhouse Structures Curtain Systems Heating Systems Irrigation Systems LED Lighting

Canadian Made, Dutch Inspired prinsgreenhouses.com | info@prinsgreenhouses.com | (604) 852-4001 Abbotsford, BC and Vineland Station, ON

GH_PrinsGreenhouse_MarApr26_BAS.indd 1

September 2026 - GREENHOUSE CANADA 51 2026-02-19 8:25 AM

that it was like, okay, maybe we better think about what role Canadians have,” she said. She served two terms, took a year off, then ran for vice‑president of the ASCFG. It was a strategic move, she said, because it meant two Canadians would sit on the board. “A northern takeover,” she jokes. Her advocacy has helped reshape how Canadian growers are seen, supported, and connected. She champions education, pricing confidence, and the message she repeats often: flowers are agriculture. “Anytime there’s an OFA thing or a Canada agriculture thing, all the pictures are vegetables and cows and chickens,” she says. “And I’m like: flowers are agriculture too!” A TRUSTED VOICE Over the years and through her advocacy, Harris has become one of the most trusted voices in Canada’s specialty cut‑flower sector not because she set out to be, but because growers kept turning to her, and she kept showing up. Her willingness to share knowledge is one of the qualities most frequently cited by fellow farmers, including Brenda Visser, who nominated Harris for She Grows and who describes her as the “Canadian face for ‘flower farmers’” and someone who “continues to break barriers” for the sector. Visser notes that Harris’ generosity shows up everywhere: in the workshops she teaches, the wedding‑design demonstrations she’s led, the farm tours she hosts, and the educational events she organizes for growers across the country. She has travelled throughout North America as a speaker,

WELCO TO BOOME TH

#1030

ADVISE, DELIVERY AND MAINTENANCE • Professional combustion systems • Central heating components • CO2 dosing systems • Remote monitoring & control • Alternative fuels

Optimal efficiency and minimum emissions YOU CAN COUNT ON OUR EXPERTISE WWW.BIGSTUFFHVAC.COM CALL: 226-237-0581 | WWW.ZANTINGH.COM TEL. +31 (0)297 219 100

52 GREENHOUSE CANADA - September 2026 GH_Zantingh_Sept26_CSA.indd 1

2026-07-29 7:40 AM

sharing insights on crop planning, greenhouse shoulder‑season management, and the realities of running a small‑to‑medium flower farm. And she’s built a digital community, too, maintaining the Canadian Fresh Cut Flower Growers Facebook page, a hub where growers exchange tips, troubleshoot challenges, and connect over everything from pest pressure to bouquet recipes. Visser notes that the page has become a vital resource, and that Harris’s “influence is broad and cannot be understated.” Visser credits Harris with strengthening the sector’s confidence and cohesion and with helping Canadian growers “claim their place” in the broader floriculture landscape. And while her advocacy is serious, Harris’s approach is anything but heavy. She leads with laughter, pragmatism, and a sense of camaraderie that resonates especially with women farmers. She’s been voted Most Popular Florist in St. Thomas, recognized as Kubota Woman Farmer of the Year (2024), and celebrated for her ability to lift others as she grows her own business. LONG HAUL For Harris, though, she sees her role as helping others build longevity, not just enthusiasm, because in her mind, mentorship isn’t about momentum, it’s about staying power. “Sustaining and staying in the business for a long time; that’s my approach to leadership,” she says. Her advice to newer growers reflects that same pragmatism: “You really have to figure out who to learn from.” In reflecting on her She Grows recognition she notes that she sees her work as part of something larger: She sees strength in the community of women growers. “Women farmers have a thing together,” she said. “We cheer each other on when we do big things.” Janis Harris’s journey from reluctant farm kid to national advocate is exactly why she stands among the inaugural She Grows honourees. What began as a few rows of gladiolus has grown into a thriving farm, a trusted voice, and a community shaped by her generosity. Through advocacy, mentorship, and a commitment to helping growers build lasting, region‑rooted businesses, she’s strengthened the confidence and visibility of Canada’s cut‑flower sector.

READ MORE ABOUT THE 2026 SHE GROWS HONOUREES

HEAR JANIS’S SHE GROWS INTERVIEW NOW

STAY CURIOUS GET THE SCOOP SUBSCRIBE NOW

Join to get our Magazine & Enewsletter

ts res insigh

profile n sha Grower s Belal El-Hassa | 14 Hendriks’ hoe production on Kalanc

of leafy

greenho

tion

duc ouse pro Greens Haven izing the greenh tion Revolu ens | 20 gre

al and bed e pH puzzl ping ornament| 28

ding

ada.com

usecan

25 MAY 20

kee Tips for perly balanced plants pro

NG FOR BLOOMOING HAUL THE L

TER REGIS S $30 to ONLY $45 SAVING HURRY! THE TO ABLE ERS AVAIL OW 100 GR FIRST REGISTER TO

WER DAY

GH_GRO

WJ.indd

ay 25_G

Cover_M

JUNE

s, o rine at h a .ca st. c e r d ay gro

PM 03 3:51

2025-041

greenhousecanada.com

GH_SUBAD_SEPT26_BAS.indd 1

September 2026 - GREENHOUSE CANADA 53 2026-08-24 1:33 PM

INDUSTRY NEWS greenhousecanada.com

GoodLeaf makes CEA history as its vertical farms across Canada reach profitability GoodLeaf Farms has become the first vertical farming operator in North America to achieve profitability across all its facilities, marking a significant milestone for the business and the CEA sector. The company, headquartered in Guelph, ON, confirmed in a recent news release that its farms in Qu<1>é<1>bec, Ontario and Alberta are now operating profitably, thanks to a boom in consumer demand for Canadian‑grown greens. “Canadians are increasingly looking for food that is fresh, nutritious and grown closer to home,” said Andy O’Brien, president and CEO of GoodLeaf Farms, in the release. “Today marks a defining moment for GoodLeaf and for the future of Canadian agriculture. Reaching profitability across all three of our farms demonstrates that vertical farming has a place in the future of Canada’s food system.” The milestone follows a period of sustained

expansion for the producer. GoodLeaf’s revenue climbed from $6.4 million in 2023 to $34 million in 2025 before rising another 31 per cent in 2026. The company credits disciplined scaling, proprietary technology and strong retail distribution for the gains. Founded in 2011, GoodLeaf operates three commercial‑scale vertical farms supplying baby greens, microgreens and salad blends across Canada. Backed by Canadian investors, including McCain Foods, Farm Credit Canada and Power Sustainable LIOS, GoodLeaf says the achievement strengthens its ability to continue expanding production and innovation while meeting rising consumer demand for fresh, locally grown produce. “With the right technology, operations and team in place, we’re proving that vertically farmed produce can be delivered at scale—and we’re just getting started,” said O’Brien. (Source: GoodLeaf Farms)

Growing is your business. Protecting it is ours! Since 1963 we have been providing high quality insurance protection to our clients from coast to coast. Experienced, local service is available through our national network of offices. For a quality product, local service and very competitive pricing give us a call today. HUB International Ontario 24 Seacliff Drive East, Unit 100 Leamington, ON N8HOC2 (800) 463-4700 hubinternational.com

Risk & Insurance

54 GREENHOUSE CANADA - September 2026 GH_Hub_MarApr23_CSA.indd 1



Employee Bene its



Retirement & Private Wealth

2023-02-23 1:10 PM

NIAGARA GROWERS CALL FOR GOVERNMENT SUPPORT FOLLOWING FLOODS The Niagara Region’s major horticultural sectors are calling for co-ordinated government support after weeks of “unprecedented rainfall events” have flooded farms, damaged crops, and disrupted normal operations across the region. A joint statement issued by Flowers Canada, Grape Growers of Ontario and Ontario Tender Fruit Growers notes how growers in the region are in a very precarious situation as they navigate an increased risk of disease pressure, plant losses and inaccessible production areas. Growers say recovery is underway but warn that the long-term impacts remain unclear. According to the release, “resilience alone will not provide the long-term stability needed for recovery and future planning.” In early August, the region, home to the largest concentration of greenhouse floriculture producers in Canada, was hit by a series of ‘100year’ rainstorms over the course of two weeks that, in areas, dropped more than 300 mm of rain.

Residents, businesses and infrastructure across the region, experienced significant flooding events, some multiple times. “Farmers will need responsive policy to help them recover from the impacts felt today, while positioning them to resume their growth trajectory for the future,” the commodity groups note in the release. The statement goes on to highlight the priority areas where government intervention is most needed: • Crop insurance changes to make vine and tree mortality coverage responsive to emergency conditions and replanting needs. • Expanded fungicide labels for drone use so growers can protect crops when flooded orchards and vineyards are inaccessible. • Flexible temporary foreign worker housing inspection deadlines to allow time for repairs and remediation. • AgriRecovery support to help farms rebuild and manage longer-term recovery costs. (Source: Flowers Canada Growers)

September 2026 - GREENHOUSE CANADA 55 GH_Reef_Sept26_CSA.indd 1

2026-08-05 GH_Pace_MarApr26_CSA.indd 1:47 PM 1

2026-02-11 2:43 PM

ed on growing silient d

g crops Growing”. iological s, and by ding

CONTINUED FROM PAGE 45 MANAGING RISK Greenhouse growers cannot eliminate every pathogen from a production system, but they can influence many of the conditions that determine disease development. Maintaining appropriate temperature and humidity, promoting air movement, reducing unnecessary condensation and leaf wetness, managing irrigation carefully, maintaining sanitation, monitoring insect vectors where relevant, and scouting consistently can all reduce disease risk. The most effective disease-management strategy is therefore not simply reacting when plants wilt. It is recognizing the environmental conditions that make disease more likely and correcting them before symptoms become widespread. Wilt may be visible on the plant, but the conditions that allow it to develop often begin much earlier. Learning to read the greenhouse environment can give growers the advantage they need to identify problems sooner, respond more accurately, and protect crop performance. Vikrant Dhawan is a plant scientist, master grower at Green Mountain Health Alliance (GMTN) and 2026 recipient of Top 4 Under 40 recognition from Greenhouse Canada. He can be reached at vdhawan@gmtn.ca. Jashandeep Singh is an assistant grower at GMTN and can be reached at Jdeep@gmtn.ca. Dr. Mohyuddin Mirza is an industry consultant in Alberta and welcomes comment at drmirzaconsultants@gmail.com. RIGHT Tomato plants showing wilting of the top.

PLANT EMPOWERMENT: THE BASIC PRINCIPLES, 2024 EDITION Scan code to buy this book

This book details how an integrated approach based on physics and plant physiology leads to a balanced growing method for protected crops resulting in healthy resilient plants, high yield and quality, low energy costs and economic greenhouse concepts. Plant Empowerment is a new approach to growing crops in greenhouses, also known as “Next Generation Growing”. It is based on a combination of physical and physiological principles rather than experiences, human feelings, and green fingers. This book aims to optimise growth by supporting the plant in keeping its balances regarding energy, water and assimilates in equilibrium. $210.00 | Item #89083371238

Educational Resources for Industry Professionals | 877-267-3473 | annexbookstore.com

56 GREENHOUSE CANADA - September 2026 GH_BOOKAD_SEPT26_BAS.indd 1

2026-07-31 10:49 AM

2026 EVENTS greenhousecanada.com

SEPTEMBER

ALBERTA GREENHOUSE GROWERS ASSOCIATION (AGGA) ANNUAL MEET AND GREET Sept. 2 Calgary, AB AGGA BOARD MEETING Sept. 3 Calgary, AB

ADVERTISERS INDEX Annex Bookstore...........................................56 Ball FloraPlant...............................................11 Ben Berg Farm & Industrial Equip. Ltd.........43 Berger Peat Moss Ltd...................................37 DeCloet Greenhouse Manufacturing Ltd.....IFC Enza Zaden Canada Inc.................................13 Exacon Inc.....................................................43

QUÉBEC ACT SUMMIT Sept. 9 St. Hyacinthe, QC

George de Groot Laser Grading & Excavating Inc.............................40

PLUG & CUTTING CONFERENCE Sept. 14 to 16 Philadelphia, PA

Jiffy Products of America Inc. / Performa.......................................................47

SAWAYA GARDENS GARDEN MUM TRIALS OPEN HOUSE Sept. 15 Waterford, ON

Koppert Canada Ltd......................................15

GREENTECH NORTH AMERICA Sept. 23 to 24 Philadelphia, PA

OCTOBER

HUB International..........................................54

Kooljet Inc.....................................................12

Lallemand Inc. / Plant Care...........................17 Lambert Peat Moss Inc. / Tourbieres Lambert Inc.................................19 Langendoen Mechanical Inc.........................44

ONE YEAR ONLY $38.00 PLUS TAX US $67.00 (USD) • Foreign $76.00 (USD)

Name: Business Name: Title:

Machinerie S.B. Inc.......................................41

Address:

Max Solutions Canada (Pkg)........................45

Prov.:

CANADIAN GREENHOUSE CONFERENCE Oct. 7 to 8 Niagara Falls, ON

N.M. Bartlett Inc............................................18

GLOBAL PRODUCE AND FLORAL SHOW Oct. 15-17 Orlando, FL

Plant Products........................................39, 48

NOVEMBER

E B I R C S B SU TODAY

Natural Insect Control (NIC).........................41 Pace Solutions Corp.....................................55

Prins Greenhouses........................................51 Proven Winners, Inc.................................5, 25 Reef Industries, Inc.......................................55

SAWAYA GARDENS POINSETTIA TRIALS Nov. 17 Waterford, ON

Rijk Zwaan Canada........................................21

GREEN INDUSTRY SHOW & CONFERENCE Nov. 18 to 19 Red Deer, AB

Sollum Technologies.....................................22

EXPO QUÉBEC VERT Nov. 18 to 20 Saint-Hyacinthe, QC

Uline Canada Corporation.............................49

HORT EAST Nov. 23 to 25 Moncton, NB

Zantingh BV...................................................52

Roam Technology NV.....................................9 Sakata Seed America, Inc...............................7

Sun Gro Horticulture................................... IBC Teris Corporation.......................................OBC

Workplace Safety & Prevention Services......................................23

Postal:

Phone: Email: Check One:

Wholesaler

Grower

Both

PLEASE INDICATE THE NATURE OF YOUR BUSINESS (Please Check One:)

Commercial Grower Commercial Grower with Garden Centre/Nursery Commercial Grower and Wholesaler Wholesaler Only Educational/Government Extension Manufacturer/Distributor Other ____________________________ Please Specify YOUR JOB TITLE (Please Check One:) Owner/President Head Grower Manager/Supervisor Sales Representative Other _____________________________ Please Specify

Payment Enclosed (Payable to Annex Publishing & Printing Inc.) Charge to: Visa MasterCard AMEX Card #: To subscribe mail to: Greenhouse Canada PO. Box 530, 105 Donly Dr. S., Simcoe, ON N3Y 4N5 Ph: (416) 442-5600 Fax: (416) 510-6875 email: subscribe@greenhousecanada.com

CANADA greenhousecanada.com

September 2026 - GREENHOUSE CANADA 57 GH_Circad_Sept26_MLD.indd 1

2026-08-19 9:41 AM

INSIDE VIEW

GARY JONES | greenhousewolf@gmail.com

The power of giving in a growing industry At the beginning of June, a very sizable cross-section of B.C.’s greenhouse industry gathered at a fabulous venue to enjoy treats, lunch, exhibits from suppliers, and a series of fascinating talks on various issues currently faced by the industry. The event was the inaugural ‘Grower Day West’, from your industry news partner, ‘Greenhouse Canada’. One of the speakers was Dr. Paul Abram from the Biological Control of Insect Pests Lab. at Agriculture and Agri-Food Canada, Agassiz, BC. His topic was ‘Stink Bugs in the Greenhouse’, and you can read more about this from Paul elsewhere in this issue of GHC. Paul beautifully described the characteristics, life cycles, signs and symptoms, and current and potential future management options of the four stink bug species in our greenhouses: Consperse (native); Conchuela (native); Brown marmorated (invasive, in B.C. since 2015); and the Southern green stink bug (invasive, first detected in B.C. 2019). The green and brown colours make identification of these ‘fun’ for colour-challenged folk like myself. Joking about Paul needing to find a yellow one so I could see it, Paul said that there is one. Of course there is. Apart from being an excellent researcher and communicator, it was clear that Paul has a real passion for his work and enjoys the connection with industry afforded by such events.

are passionate about their chosen work subjects, have become experts in their fields, and yet always have time to share their knowledge and skills with others. The ‘community’ of horticulture is something that makes this a ‘stand out’ career choice. Early in October, many will gather in Niagara Falls to enjoy the annual Canadian Greenhouse Conference (CGC). Apart from 82,000sq.ft. of exhibitor space to explore the latest and greatest new tech, and preevent bus tours, there will be two days of educational presentations across a huge variety of topics. Great information, well delivered, and fun times with colleagues and partners. Sign up now. So what? What’s the connection? Well, if you’re one of our more ‘experienced’ industry members, perhaps take a few minutes to reflect on your own career. Can you, like Ronald, give a shout out to people who were your support and champions during your early career? I recall working in the vegetable garden with my grandfather and being amazed at how a little seed put in the ground would magically turn unseen into a delicious orange carrot but just a few weeks later. That was my initial spark. And being inspired by my biology teacher at school whose enthusiasm for the subject was just, well, infectious. Or do you remember a presentation you attended, like Paul’s perhaps, that was clear, informative, captivating, and ‘made the penny drop’ for you about a particular topic? Despite all the ‘advances’ of AI, we all still connect with real people Better still, are you or can you be deliberate in being a supporter of A short while ago, I enjoyed a post on ‘LinkedIn’ someone starting their own journey, or even just on from Ronald Valentin, Director, Corporate IPM the fringes looking in at this point? Despite all the at Mastronardi Produce. Ronald was celebrating: ‘advances’ of AI, we all still connect with real people, “Grateful is the word that enters my mind today. Today, and like Ronald, we may tip our hats to those around exactly 40 years ago, June 9th 1986, I was given the us who’ve been those critical connections. If you’re opportunity to start working in this wonderful world heading to CGC in October, of course you’ll be going called Biological Control. I am grateful for the many with a view to get something out of the time you put people I have met on this journey. There are too many to in. But maybe it’s equally an opportunity to give back mention.” He takes a moment to salute many of those and see who you can inspire. Then, don’t just stop who influenced his career over the years. Those of you with your time at CGC - aim to be inspirational in fortunate enough to know Ronald, will recognize that your daily work walk. when he says such things, it comes from a place of honesty and integrity. Gary Jones has worked in many aspects of the We’re an industry really blessed to have so many horticulture industry in BC, the UK, and elsewhere, and colleagues and partners, who like Paul and Ronald, welcomes comments at greenhousewolf@gmail.com.

58 GREENHOUSE CANADA - September 2026

Built to Outperform.

Sun Gro® Black Bear® is different than most biochar products, our biochar is an aggregate not an additive – engineered for high performance. Delivers perlite-like aeration Course particle size to provide drainage Helps hold nutrient in the root zone

Don’t take our word for it – sign up for your

FREE TRIAL TODAY! September 2026 - GREENHOUSE CANADA 59

60 GREENHOUSE CANADA - September 2026