Arboretum Magazine Fall 2025

This Page Aster blooms in Spring

September.

ON THE COVER

ARBORETUM

MAGAZINE

FALL 2025, VOL. 44, NO. 3

Celebrating the research at the Arboretum’s core

Mediterranean roasted carrot salad

Elise Bremer Editor

Brenda Drake Lesch

Art Director

Andrew Gapinski Executive Director

Matthew Clark, Ph.D. Director of Research

Rachelle Crosby Director of Facilities & Project Management

Timothy S. Kenny Director of Education

Jared Rubinstein Director of Horticulture & Collections

David Senior Director of Business & Finance

Susan Taylor, Ph.D. Director of Advancement

Tom Lany

Senior Marketing & Communications Manager

Kathy Persian President, Arboretum Foundation

Arboretum Magazine is published by the University of Minnesota Landscape Arboretum. The Arboretum is part of the College of Food, Agricultural and Natural Resource Sciences (CFANS) at the University of Minnesota. The magazine is a benefit of Arboretum membership. To request a copy of this publication in an alternate or digital format, please call 612-301-1257.

© 2025 Regents of the University of Minnesota. All rights reserved. The University of Minnesota is an equal opportunity educator and employer.

arb.umn.edu 612-624-2200 arbpr@umn.edu

Arboretum Magazine is printed on paper containing 100% sustainable recycled fiber.

Autumn is one of my favorite times of year at the Arboretum as we welcome visitors to celebrate the beautiful display of fall color throughout our collections and natural areas; the arrival of pumpkins, squash and gourds to the Arboretum and AppleHouse; and of course, the season of all things apple.

Beloved apples, such as the Haralson, Honeycrisp and most recently, Kudos®, were developed in the orchards surrounding the Arboretum. For more than 100 years, the Arboretum’s Horticultural Research Center (HRC) has been the home of the University of Minnesota’s fruit breeding and horticultural research conducted in partnership with the Department of Horticultural Science.

In addition to apple and fruit research, the HRC is the site of ornamental and woody plant research that has brought numerous cold-hardy azaleas, roses, ornamental trees and more to gardens throughout the region. These plants are thoroughly tried and tested at the Arboretum and have provided ideas and inspiration for cold-climate gardeners for decades.

This year, woody plant researcher and professor Stan Hokanson is retiring after a 24-year career at the U of M, and the lasting impact of his plant breeding and research can be seen across the Arboretum landscape. You can learn more about his career and contributions on page 10.

As we continue to Build a Better Arboretum for our community — with a New Entry Experience and Betty’s Apple House slated to open in 2027 — we’re also finalizing the Arboretum’s 2025-2030 strategic plan. The new strategic plan includes key strategic initiatives and projects that will guide the Arboretum’s work for the next five years and onward toward our vision for the future. I look forward to sharing it with you soon.

Thank you to the Arboretum members and supporters who make our work possible. See you at the Arboretum this fall!

Andrew Gapinski

Sugar

(Acer

) light up

The Science Behind Minnesota’s

FALL SPLENDOR

Experts at the University of Minnesota explain why leaves change color in the fall

Arboretum staff recommend a trip to the Farm at the Arb to view the rich red autumn foliage of the ‘Brandywine’ red maple trees, located along Peter C. Moe Drive and behind the Red Barn.

In Minnesota, autumn offers a brilliant, fleeting transition between the sweltering days of summer and the long, cold nights of winter. For a few magical weeks each year, crisp air carries the scent of fallen leaves across the state, with maples ablaze with crimson and oaks radiating a golden hue.

As both a scenic escape and a hub of horticultural research, the Arboretum offers the perfect vantage point to explore what makes Minnesota’s array of fall colors so dazzling and dynamic. Why do leaves change color in the fall? And why are some years more spectacular than others?

Minnesota’s Autumn Palette

“Shorter days and cooler temperatures signal trees to prepare for winter by conserving energy and water,” explained Eli Sagor, Extension Forestry Specialist and Professor at the University of Minnesota’s Cloquet Forestry Center. And according to Jessica Savage, Associate Professor and Plant Physiologist at the University of Minnesota Duluth, this process leads chlorophyll, the culprit behind the green hue of deciduous plants, to break down. In many species, leaf color change is due to the loss of

chlorophyll, which reveals colors that were previously masked by the green, such as yellow, brown or orange. Yellow and orange leaf colors come from carotenoid pigments, which are always present in leaves and break down more slowly than chlorophyll, said Laura Irish-Hanson, an Extension Horticulture Educator based at the Arboretum.

But some species accumulate anthocyanins, pigments that produce red or purplish hues. Their production depends on high sugar levels in the leaves, which are boosted by sunny, warm days and retained by cool nights that slow down sugar transport. This sugar buildup triggers anthocyanin formation. When this ideal weather combination occurs, trees are more likely to show vivid reds. Without it, red pigments may not develop.

According to Irish-Hanson, the two biggest factors influencing a tree’s autumn color scheme are shortening day length and declining temperatures. But the process begins long before the leaves start to change. “A warm, wet spring sets the stage for a brilliant fall,” said Sagor. Adequate rainfall throughout the summer, especially late in the season, keeps leaves healthy, supporting brighter yellows, oranges and reds.

Climate change is already reshaping this delicate process,

however. According to Brandon Miller, Assistant Professor of Horticultural Science and Curator of Plant Collections at the Arboretum, the unpredictable and extreme weather caused by climate change can delay and dull the intensity of fall leaf color. Sagor confirmed that warmer weather can delay the start of color changes, making leaves stay green longer, shortening the timing window for vibrant foliage, and dulling its intensity. Sagor also said drought-stressed trees often produce fewer pigments, even when a drought hits early in the growing season. On the other hand, he noted that excessive rainfall can cause early leaf drop or even kill sensitive species. Overly warm fall nights can also interfere with anthocyanin production, resulting in less vivid reds and purples. As a result, autumnal colors may arrive later, fade faster and lose some of their brilliance.

Still, nature keeps us on our toes. “Some plants may exhibit more intense color changes when stressed,” said Irish-Hanson. But the most reliable recipe for spectacular fall foliage remains the same: a healthy growing season followed by sunny days and crisp autumn nights.

Where to See the Show

Although maples, oaks and serviceberries certainly put on a show at the Arboretum, fall color isn’t just about the forest canopy. Shrubs add rich reds and purples to the landscape, with some showcasing vibrant stems as well as leaves. “Often trees get more attention, but sumac, dogwood and Virginia creeper are some of my favorites,” said Savage. For a few standout specimens at the Arboretum, IrishHanson and Miller both recommend the ‘Brandywine’ red maples located near the Farm at the Arb and the colorful trees in the Oak and Nut Collection. Miller also called out the longstanding black tupelo trees in the Pillsbury Shade Tree Exhibit, known for their fiery red leaves, as a highlight. Arboretum staff also encourage visitors to explore the Ornamental Grass Collection in the fall, where color and texture combine

to create an enchanted seasonal landscape.

Although unpredictable weather makes it difficult to pinpoint when peak leaf color will strike, Miller said, “I recommend visitors follow the Arboretum on social media and subscribe to our communication channels to receive the most up-to-date information on the best times to visit.” Miller also highlighted the Minnesota DNR’s Fall Color Finder, which provides weekly updates on the progression of fall color throughout the state. So on your next visit to the Arboretum this autumn, take a moment to observe and appreciate the science behind the ephemeral transformation of our trees.

What Paints the Leaves: Key Pigments of Autumn

According to Eli Sagor, Extension Forestry Specialist and Professor at the University of Minnesota’s Cloquet Forestry Center, four pigments play a vital role in leaf color change each fall.

Chlorophyll is central to the process of photosynthesis, allowing plants to convert sunlight into energy. As fall approaches, chlorophyll breaks down, stripping away a leaf’s green pigment and revealing others that have not yet broken down.

Carotenoids are always present in leaves but become visible when chlorophyll breaks down. They play a crucial role in photosynthesis by capturing light energy.

Tannins become visible when both chlorophyll and carotenoids break down. They are more prominent in some species, such as oaks, than in others, such as maples.

Anthocyanins build up in some leaves from sugars trapped inside. The resulting leaf color can vary between reds and deeper purples, depending on the pH of the leaf cells.

When leaves begin to fall, take this scavenger hunt to the Arboretum to test your tree knowledge! How many leaves shown on this page can you find across the landscape? As you find a match for each leaf, write its location on the page.

Acer saccharum

In the spring, the Arboretum taps 400 sugar maple trees that produce more than 6,000 gallons of sap! The sap is processed into syrup at the Maple Sugar House in Frog Hollow.

Location:

Aesculus glabra

What’s a buckeye? This tree gets its name from the resemblance of the nut to the eye of a male deer, or buck. Look for nuts on the ground to help find this tree!

Location:

Quercus alba

The wood from white oaks is strong, durable and water-resistant and has historically been used for shipbuilding.

Location:

Ginkgo biloba

Ginkgo biloba is one of the oldest living tree species in the world and was around before the dinosaurs. It’s known as a “living fossil”!

Location:

Liriodendron tulipifera

The tuliptree is one of the largest native trees in North America and is named for its distinctive tulip-shaped flowers that form in late spring.

Location:

Birds of a Feather

Julie Peters l Communications Strategist

For Arboretum member and volunteer Ginger Eddy, 83, the Arboretum has provided a place for connecting, learning and giving back.

In fact, when Eddy returned to Minnesota after living in Michigan for 15 years, the Arboretum was one of her first stops. “I signed up for a class,” she said, adding she doesn’t recall if it was a class in gardening or art — she’s participated in so many over the years! She became an Arboretum member in 2002 and joined the Arboretum Auxiliary, which has been the ideal outlet to share her skills and creativity.

She may be best known for the birds she knits and felts for Auxiliary craft sales. “We’ve sold 449 to date,” she said, noting that proceeds go back to the Arboretum. “The cardinal is my best seller.”

There’s also a chickadee, owl, robin, woodpecker and more — 13 Minnesota bird varieties in all. Each one can take four hours to make. She carefully knits, felts and stuffs the bodies, then needle felts to add more details, before attaching eyes and a beak.

Eddy’s creativity doesn’t stop with birds. She knits hats and scarves, paints, and creates jewelry out of birch bark and repurposed beads. “I like the challenge,” she said. “It brings out my creative side to find what I can make out of other things.”

Growing up, Eddy said her mother instilled in her a love for crafts with leatherwork and stenciled art. Graduating with a home economics education degree from UW-Stout, Eddy would go on to work as an Isanti County Extension agent. Later, she operated a decorative paint business for 10 years.

Auxiliary Events

Learn more about upcoming events hosted by the Auxiliary in support of the Arboretum at arb.umn.edu/events/topics/auxiliary

Arboretum Glass Pumpkin Patch

Sept. 12-14 (Opening Night Sept. 11)

Auxiliary Harvest Sale

Oct. 3-5

Auxiliary Quilt Raffle Fundraiser

Drawing Oct. 4

Auxiliary Holiday Sale

Dec. 5-7

Eddy’s crafts are sold at Auxiliary sales throughout the year. While she appreciates that she can help the Arboretum this way, she’s gained just as much in return. “I found volunteering to be a good way of connecting with people when I moved back from Michigan,” she said. “It’s a way to make friends and do interesting things.”

And to be able to volunteer in a place that has given so much back to Eddy, she said it has been a joy. “It’s a pure pleasure to come here.”

(Above) Volunteer Ginger Eddy found community — and an outlet for her creative talents — in the Arboretum Auxiliary. Photo by Julie Peters

Growing giant pumpkins at the Arboretum

Derek Carwood Adult Education Manager

From Seed

he Arboretum is no stranger to growing unique, quirky and uncommon plants. Some, however, hold such special significance that they warrant a return to the grounds, even when they require a bit of extra care — and a whole lot of space. Enter the giant pumpkins!

While technically more closely related to winter squash than to the traditional carving pumpkins (Cucurbita pepo) that fill porches at Halloween, giant pumpkins (Cucurbita maxima) have an almost fantastical appearance — grotesque gourds straight from the imagination of Lewis Carroll. These pumpkins aren’t grown for eating, but for size. And in the world of giant pumpkin growers, bigger is always better.

After a three-year hiatus, the offspring of Audrey and Seymour — the giant pumpkins previously grown at the Arboretum in 2022 — are back. This time, they’re planted front and center at the Farm at the Arb across from the Burton and Virginia Myers Education Center. Supported by the Arboretum’s pumpkin and squash experts John and Jenny Thull, this year’s goal is to grow the largest pumpkins possible, right alongside crops including popcorn, Kernza®, potatoes and sugar beets. As the Arboretum’s hub for agricultural education, the Farm is the perfect site to showcase cultural practices used by

both horticulturists and farmers to cultivate a wide variety of crops, including these massive squashes.

Giant pumpkins demand more attention and care than their traditionally sized cousins. Due to their extreme nutrient and space demands, growing them requires careful planning, but with the right care and a sufficiently large garden, anyone can try their hand at growing a super squash at home.

Several large pumpkin cultivars are available commercially, such as Dill’s Atlantic Giant® and ‘Big Max’, but the true giants are often hobby-grown varieties. These are shared and passed down among serious growers, who compete to break records and wow crowds with their horticultural prowess. If you’re looking for local seed sources, the St. Croix Growers Association is a great place to start; their seeds routinely outperform commercial cultivars.

Before planting, it’s important to analyze your soil. Aim for loamy soil with a pH between 6.0 and 7.5, and an organic matter percentage between 5% and 10%. Amending your soil with composted manure or leaf mold can help boost both fertility and structure, which are key to supporting vigorous vine growth. Minnesota’s short growing season means pumpkins need to absorb nutrients quickly and efficiently, so regular amendments throughout the season can make a big difference. To support

to Spectacle

this rapid development, plants must receive at least eight hours of full, unobstructed sun per day.

Giant pumpkin seeds should be started indoors before the growing season to give them time to mature and begin fruiting. However, care is needed when transplanting seedlings as pumpkins dislike having their roots disturbed. Using biodegradable pots can help reduce transplant shock. Once planted outdoors, they need constant watering, regular fertilization and protection from pests to support their growth into true giants.

Throughout the growing season, it’s crucial to check for pests and diseases. In the Midwest, squash vine borers — the larvae of the native clearwing moth — will wreak havoc on pumpkins. Regularly checking for larvae growing within the vines and doing a bit of surgical excision is vital to long-term vine health and, ultimately, the ultimate pumpkins.

As mentioned, the Arboretum’s expertise in pumpkins and squash is longstanding. John and Jenny Thull are viticulturists at the Horticultural Research Center (HRC) at the Arboretum and manage the acres of vineyards for the University’s grape breeding and enology project. In the months leading up to the harvest season, John and Jenny — who met at the HRC in 2006 and have been married 13 years — also plant and grow the

(Far Left) Derek Carwood, Adult Education Manager, checks on this year’s giant pumpkins at the beginning of the growing season.

(Left) In 2022, Associate Extension Professor and Educator Julie Weisenhorn and a team of Extension experts grew two giant pumpkins at the Arboretum in a fenced plot across from the Chinese Garden. Photo courtesy of Julie Weisenhorn

pumpkins, squash and gourds that are used in the Arboretum’s seasonal displays and sold at the AppleHouse.

Over the years, they’ve expanded the Arboretum’s decorative pumpkin, squash and gourd program, this year planting 510 unique cultivars, including new, festive pumpkin varieties. According to Jenny, “Yellow pumpkins are becoming the new orange and brown or neutral pumpkins are becoming all the rage for home decorating.” Visitors can expect to see many trendy pumpkin cultivars available at the AppleHouse this year, including ‘Hot Chocolate’, ‘Grizzly Bear’ and ‘Spicy Mocha’.

As always, the mission at the Farm at the Arb is to shine a light on agricultural education by growing some of Minnesota’s most economically important crops alongside those that represent the future of farming. With the Tashjian Bee and Pollinator Discovery Center and the Farm’s newest addition — the Burton and Virginia Myers Education Center — the Farm has become the heart of adult education at the Arboretum. Hundreds of hands-on classes in cooking, art, photography, and of course, horticulture now take place in this vibrant, easily accessible space. Stop by the Farm on your next visit to the Arboretum this season to check the progress of the giant pumpkins and discover how agriculture, education and inspiration grow together at the Arboretum.

It’s All Coming Up (With) ROSES

Celebrating the impact of a 24-year career in woody plant breeding and genetics

Elise Bremer l Editor

Stan

(Left) After a fruitful career developing cold-hardy woody and ornamental plants at the University of Minnesota, Stan Hokanson is retiring.

(Right) Brandon Miller, Assistant Professor of Horticultural Science and Curator of Plant Collections at the Arboretum (left), and Stan Hokanson in the advanced selection azalea trial plot at the Horticultural Research Center.

Looking back on Professor Stan Hokanson’s early days growing up near Sawyer, Mich., it’s easy to see how he fell into a life devoted to plant research. Located in temperate USDA Hardiness Zone 6, the area of southwest Michigan was once a major hub of fruit production as well as an early center of the mail-order nursery business.

An avid gardener from a young age, Hokanson remembers “conning” his mom into taking him to the garden center to buy new landscape plants for the family home.

Now, after a career devoted to plant breeding and genetics — including the last 24 years spent in the Department of Horticultural Science at the University of Minnesota — Hokanson is retiring,

later traveled to Kazakhstan to study the country’s wild apples. On the trip, Hokanson spent time with Harold Pellett, a U of M professor and plant breeder whose work developing woody trees and shrubs at the Horticultural Research Center (HRC) at the Arboretum widened the palette of coldhardy landscape plants available to gardeners in Minnesota and other cold climates.

To Hokanson, the job sounded like a dream, and he resolved to apply for the role upon Pellett’s retirement. After another few years researching small fruits at the USDA in Washington, D.C., Hokanson learned the position was available. He applied for the role and started at the U of M in 2001.

University of Minnesota

While the opportunity to develop cold-hardy plants and teach aspiring horticulturists was tantalizing, Hokanson had to carefully consider what the impact of the work might be. After all, he had spent his early career devoted to “saving the world” by striving to develop plants that would result in

One of the greatest joys of Hokanson’s time at the U of M was teaching and advising students pursuing their own careers in horticulture.

leaving behind a legacy with a lasting impact on gardens throughout the region and on countless former students.

From Michigan to Kazakhstan

While Hokanson’s tenure at the U of M has led to the introduction of numerous woody and ornamental landscape plants, his early career spanned multiple areas of horticultural research.

Nearing the end of a Ph.D. at Michigan State University studying gene flow in transgenic plants, Hokanson had what he calls his “NPR moment.” A visiting lecturer presented research tracking the gene spread of domesticated dogs into endangered, wild dog populations using a

new genetic marker system called simple sequence repeats (SSRs).

“When I heard that, I was like, ‘That’s exactly what I needed to do all the work I’ve done … that would have been perfect,’” said Hokanson.

A short time later, Hokanson and his wife Karen were listening to NPR on their way home from work and caught a segment about endangered wild apple forests in Kazakhstan that researchers at Cornell University were studying.

“I told Karen, ‘When I finish my Ph.D., I am going to write those guys a letter, I could study those wild apple populations with the SSRs.’”

Hokanson headed to Cornell and

cheaper, more efficient food production.

Considering the joy Arboretum visitors and home gardeners derive from the vibrant cold-hardy azaleas, roses and more developed during Hokanson’s time at the U of M, the impact of his work on gardens and gardeners alike is clear.

In addition to introducing many plants for cold climates, Hokanson’s lab published key research involving genetic resistance to rose black spot, the most important fungal disease affecting roses worldwide. The longrunning project has identified four resistant genes in roses, and the team is now in the process of developing markers linked with those genes so that

breeding of disease-resistant roses can be done more efficiently.

All of this, Hokanson reflected, would not have been possible without the work of numerous colleagues and collaborators, including Steve McNamara, a project scientist at the HRC who is responsible for managing field trials and more.

“He’s done the majority of the crosses, cold hardiness screening, he’s great with plant propagation and he’s been here just about 40 years,” said Hokanson. “He’s a fantastic plants person.”

Due to the long-term nature of woody plant breeding, many introductions take up to 20 years before they reach consumers. That means some of the projects that Hokanson and McNamara collaborated on are just now getting ready to hit the market, including new elderberry, forsythia, redbud and weigela introductions.

“I think we’re both proud of these plants and the work we and our project crew put into creating them,” said McNamara.

Leaving a Lasting Impression

One of the greatest joys of Hokanson’s time at the U of M was teaching and advising students pursuing their own careers in horticulture. Having been a “non-traditional student” who started graduate school later himself, Hokanson resolved to bring empathy for all kinds of students to his teaching, and to encourage his students to pass that kindness along in their careers.

“We can develop plant cultivars and put them out there, but I’ve got a couple of students in academia now that graduated out of my lab, and I think about how many students have graduated out of their labs. It just keeps multiplying, and the impact is so great,” said Hokanson.

In retirement, Hokanson plans to enjoy more time with his family, including his new grandson, and spend time outdoors in the garden, biking, Nordic skiing and fishing.

Hokanson Highlights

Find a few of the woody landscape plants introduced during Hokanson’s career here and across the Arboretum landscape in the spring. For more detailed plant locations, head to the Plant Finder on the Arboretum website at arb.umn.edu/plant-finder and search by plant name.

Suddenly SummerTM Summer Waltz Rose

Nelson Shrub Rose Garden

• Double-cupped, medium pink, frilly 3.5-inch blooms with light fragrance

• Released exclusively at the Arboretum Plant Sale in 2012

Electric LightsTM Double Pink Azalea

Woodland Azalea Garden

• Fragrant, light pink, double-flowering blooms that last for seven weeks

• Green foliage deepens to burgundy in the fall

• Buds are hardy down to minus 30 degrees Fahrenheit

• Released in 2015

Electric LightsTM Red Azalea

Woodland Azalea Garden, Bailey Shrub Walk

• Fiery red blooms appear in early spring after new foliage appears

• Buds are hardy down to minus 30 degrees Fahrenheit

• Released in 2015

True North™ Kentucky Coffeetree Near the Iris Pond

• Notable for its narrow, upright-oval form and superior branch architecture

• Male specimen; doesn’t produce seed pods

• 20-30 feet wide by 50-70 feet tall

• Released in 2015

Heart’s Desire™ Redbud

Pillsbury Shade Tree Exhibit

• Lavender pink, May flowers are followed by medium green foliage in summer and yellow foliage in the fall

• Heart’s DesireTM redbud was selected from a group of consistently cold-hardy, openpollinated seedlings growing in the Arboretum’s Shade Tree Exhibit

• 15-20 feet tall by 20-30 feet wide

• Released in 2019

AUTUMN GOLD

Matt Schuth is a naturalist and author of “Nature at Our Doorstep.” He has contributed a nature column to Arboretum Magazine for more than 30 years and hosts seasonal guided “Walks With Matt” exploring the natural world at the Arboretum.

WSchuth holds up a honey mushroom during a mushroomthemed session of his popular Arboretum class “Walks With Matt.”

hen the cooler days of autumn arrive and the forest becomes a kaleidoscope of scarlet reds, flaxen yellows and golden oranges, a myriad of mushrooms seem to appear overnight as if by the work of whimsical fairies.

One of the mushrooms most sought after by fanatical fungi foragers is the honey mushroom (Armillaria mellea). Honey mushrooms can feature a variety of colors, ranging from honey yellow and tan to pink-brown with reddishbrown, cottony scales. Honey mushrooms have a slightly sweet to nutty flavor; they are not poisonous but are mildly toxic if eaten raw. An old adage to remember when foraging is that “there are old mushroom hunters and bold mushroom hunters, but there are no old, bold mushroom hunters.”

Matt Schuth l Naturalist

The largest living organism in the world — a colony of Armillaria ostoyae in the Malheur National Forest in Oregon — is a relative of the honey mushroom.

Honey mushrooms can be found growing in massive colonies on living hardwoods, stumps and buried wood. The mushroom’s spores produce long, black, root-like structures called rhizomorphs. They can grow a great distance through the soil until they find a host to parasitize. In an ironic twist of nature, the parasitic honey mushroom is attacked by Entoloma aborvitum, another parasitic mushroom which consumes it.

The mycelium (roots) of honey mushrooms have a bioluminescence called foxfire, which was once used to illuminate submarine compasses. The fungus is also prized for its medical qualities. In traditional Chinese medicine, tablets containing honey mushroom mycelium were used to treat a variety of neurological conditions, including vertigo, hypertension, epilepsy and insomnia. It has a strong action against certain bacteria, including Streptococcus and Staphylococcus. A recent study found that honey mushrooms contain certain polysaccharide compounds that decrease the buildup of specific proteins in the brain linked to Alzheimer’s disease.

The largest living organism in the world — a colony of Armillaria ostoyae in the Malheur National Forest in Oregon — is a relative of the honey mushroom. It covers an area of 2,400 acres and is estimated to be between 1,900 and 8,650 years old. This is nature’s true Methuselah. Volunteer Karen Sowizral has photographed 250 species of mushrooms that we have identified at the Arboretum. Enjoy the beauty and uniqueness of our mushrooms, but remember, no foraging at the Arboretum.

HOSTAS Were But a Beginning

Jeff Iseminger l Contributing Writer

One of the first dates that Elaine and Foster Cole ever had — one that has set a horticultural tone for their 33 years of marriage — involved marinated chicken, Doritos and a huge helping of hostas, all at the University of Minnesota Landscape Arboretum.

“I thought Elaine would enjoy seeing the hosta collection,” said Foster, who started coming to the Arboretum as a kid with his parents in the 1970s. “He even packed a picnic basket for us,” said Elaine with a smile. “He really had it all working.”

Since that date they’ve embedded — Foster called it “hard-wired” — the Arboretum into their seasonal calendar. They revel in everything Arboretum-y, including Winter Lights in the colder months and crabapple blossoms and peonies in the spring and summer.

“We also love to bring visitors to the Arb so we can show it off,” said Elaine. It’s one thing to be proud of the Arboretum, but it’s quite another to invest time and treasure to ensure that its glories not just survive the travails of time, but thrive.

For one big example, the Coles have incorporated the Arboretum into their estate planning. That means they’re

members of the Leon Snyder Heritage Society for planned giving.

“The Arboretum has a certain permanence,” said Elaine, “so Foster and I feel good about investing in its future.” In other words, the Arboretum’s strength over time galvanizes support, which in turn amplifies that robust continuity.

“The Arboretum has done a good job in keeping in touch,” said Foster. “The ball never gets dropped, and that’s important to us.” In contrast, he added, a few nonprofits they’ve supported have taken a “you-give-andthen-we-forget” approach.

The Coles have also engaged with the Arboretum through its Annual Fund, the Gala, Taste & Toast and travel programs. Elaine’s late mother, Arleen Ballor, caught the travel fever, too: “Oh, she must have gone on a dozen Arboretum trips,” said Elaine. For her and Foster, their own

travel — “We just enjoy doing things together,” she said — often focuses on a definitive destination: gardens, especially English gardens. In fact, they’ve taken 10 trips to England to see such National Trust gardens as Woolbeding in West Sussex, Sissinghurst in Kent and Hidcote in the Cotswolds.

Every time they visit a National Trust garden, they have tea and scones or a slice of coffee walnut cake. They also love to savor English cheese; after all, this is a country with villages called Cheddar and Stilton and a regional cheese like Double Gloucester.

The Coles said they can now enjoy that same superb gardens-and-food experience at the Arboretum. “There is great new food at the Rootstock cafe,” said Foster. Rootstock, which opened in the summer of 2024, is led by the culinary team of Chefs Beth Fisher and Niki

Heber and features farm-fresh, plant-forward menu offerings inspired by the season.

Here’s one of many scenarios: After walking through the Kitchen Herb Garden, you can taste how good herbs can be at Rootstock in quiche Lorraine with bacon and gruyere cheese or perhaps house-made soup with focaccia and olive oil or Romanstyle pizza al taglio. That’s a long, long way, culinarily speaking, from crunching Doritos among the hostas.

So take it from two Anglophile garden-lovers, what the Arboretum offers is utterly unique, in and of its beautiful self. “You don’t see it anywhere else,” said Elaine. “It’s really such a treasure. That’s why I tell visitors, ‘Look what we have here!’”

The Coles have also engaged with the Arboretum through its Annual Fund, the Gala, Taste & Toast and travel programs. Elaine’s late mother, Arleen Ballor, caught the travel fever, too: “Oh, she must have gone on a dozen Arboretum trips,” said Elaine.

AT THE ARBORETUM’S CORE

When the leaves begin to turn brilliant shades of orange, yellow and red, and the air grows crisp with the first signs of fall, one thing is on the minds of many Minnesotans: biting into a fresh, locally grown apple. At the Arboretum, one bite of a juicy red apple isn’t just sweet, it’s a bite into a piece of history.

The apple excitement comes to life each year at Apple Fest, the ultimate celebration of Minnesota’s favorite fall fruit. Happening on Sept. 27 at the Arboretum, Apple Fest offers the perfect opportunity for visitors to savor the

fall season, enjoy apple-inspired treats and delve into the legacy of some iconic University of Minnesota apples.

The U of M is recognized as one of the top apple breeding and genetics research programs in the country and has introduced many beloved apples, including Haralson, Honeycrisp, SweeTango® and most recently, Kudos®. The heart of the apple breeding program is the Horticultural Research Center (HRC) at the Arboretum, located just 1.5 miles west of the Arboretum’s main entrance near the AppleHouse. In the orchards surrounding the HRC and Arboretum, apple trees are grown and carefully

The highlight of Apple Fest is the apple-themed trivia competition, where visitors can test their knowledge against the Arboretum’s apple experts.

evaluated by researchers in pursuit of the next great apple.

The Arboretum’s heritage as a trendsetter in plant research began in the early 1900s when the researchers’ singular task was to develop apple varieties that could survive in Minnesota’s cold climate. The first apple breeders took inspiration from Russia, a region with similarly challenging weather conditions. Later, apple breeders collected seeds from New England and other cold climates and grew thousands of trees for evaluation. Some progeny of Malinda, a New England variety, survived and led to the successful apples released in the 1920s, including Haralson and Beacon. Since the early days of the breeding program, researchers at the HRC have developed some of the world’s most well-loved apples, including the iconic Honeycrisp.

On average, developing a new apple can take 20 to 30 years and involves a rigorous evaluation process to ensure a high-quality fruit reaches consumers. Year one begins with choosing the parent trees using data on their horticultural performance as well as DNA testing. Multiple pairs are made, and hand pollinations result in nearly 10,000 seeds each year. The trees are grown, and then sampled and tested for as long as two decades. In the final five to 10 years, commercial nurseries propagate trees for the mass production of the fruit.

So this fall, celebrate these remarkable introductions right where they were developed, at the home of the Honeycrisp! Apple Fest features a day of fun and educational apple-centric activities for visitors of all ages to enjoy. Visitors can compete in the longest apple peel competition and applesauce-eating contest and “bob” for apples before learning more about the history of Minnesota apples during expert-led talks.

“It’s so fun to watch everyone running around celebrating apples,” said Wendy Composto, the Arboretum’s Signature Events Manager and creator of Apple Fest. “The kids play games and have an absolute blast. The apples here really bring everyone together for a fun family day.”

A highlight of the event is the applethemed trivia tournament, where participants can compete against the Arboretum’s apple experts. Winners will take home exciting Arboretum-themed prizes, including tickets to the Fall Color Run, Full Moon Hikes and even Winter Lights.

Hungry for apples? For an apple-themed snack, visitors can stop by Rootstock concessions for apple-y treats or vote on mouth-watering baked goods in the Apple Fest baking contest. Tastings of locally grown apples are on the menu as well. Visitors can choose their favorite variety before heading to the AppleHouse to grab a bag.

University of Minnesota Apple Varieties

Celebrate the taste of the season with apples developed at the Horticultural Research Center at the Arboretum. Find a few highlights here and head to mnhardy.umn.edu/apples for more information about the University’s breeding program.

FIRST KISS®

• Juicy, tart, deeply colored

• Ripens early

• Stores for up to five months

• Parentage: Honeycrisp and AA44

HARALSON

• Firm, tart flavor

• Good for cooking, especially apple pie

• Stores for four to five months

• Parentage: Malinda and Wealthy

HONEYCRISP

• Outstanding crispness and juiciness

• Best for fresh eating

• Stores for seven or more months

• Parentage: Keepsake and unknown

KUDOS®

• Juicy texture and sweet flavor

• Tropical overtones

• Stores up to five months

• Parentage: Honeycrisp and Zestar!®

SWEETANGO®

• Sweet hints of fall spices

• Deep red coloration over a yellow breaking background

• Crisp texture and juicy

• Parentage: Honeycrisp and Zestar!®

Taste the legacy of more than 100 years of apple research at Apple Fest on Sept. 27 from 10 a.m.-4 p.m. Apple Fest is included with general daily admission. For more information, visit arb.umn.edu/applefest. Participants compete to produce the longest apple peel at Apple Fest in 2023.

The AppleHouse, which is located just 1.5 miles west of the Arboretum’s main entrance and opens this year on Aug. 21, is the go-to fall destination for all things apple and autumn! The shelves are packed with seasonal decor, gourmet goodies and Minnesota-grown apples. Plus, visitors can shop pumpkins, squash and gourds grown right at the Arboretum. No admission ticket is required to visit the AppleHouse.

MEDITERRANEAN ROASTED CARROT SALAD

Serves 2-3

This seasonal recipe by Rootstock Executive Chef Niki Heber puts a spin on dukkah, a traditional spice mixture used in Egyptian and Middle Eastern cooking which typically uses tree nuts. For this recipe, Chef Niki swapped out the nuts for sunflower seeds, making the dish nut-free.

INGREDIENTS

2-3 medium carrots, cut into irregular shapes

12-ounce can of chickpeas

Neutral cooking oil

Kosher salt

½ seedless cucumber, cut into irregular shapes

Sweety drop peppers and radish sprouts to garnish

Cucumber yogurt

1 cup full-fat Greek-style yogurt

½ cup finely diced cucumber

¼ cup finely diced red onion

1 tablespoon finely chopped dill

1 tablespoon finely chopped parsley

1 teaspoon kosher salt

½ teaspoon ground black pepper

2 teaspoons lemon juice

Sunflower seed dukkah

½ cup sunflower seeds

1 tablespoon whole fennel seeds

¼ cup white sesame seeds

1 teaspoon ground cumin

1 teaspoon ground coriander

1 tablespoon kosher salt

SUBSTITUTIONS

• Carrots: For a seasonal twist, you can use roasted squash, sweet potatoes or most root vegetables in place of carrots.

• Sunflower seeds: Use any nuts. Pecans work great.

• Radish sprouts: Any sprout or herb, such as dill.

• Sweety drop peppers: Any canned or jarred pepper, such as peppadew.

PREPARATION

Mix together the ingredients for the cucumber yogurt and let it marinate overnight in a sealed container.

When you are ready to prepare the roasted carrot salad, preheat the oven to 400 degrees.

Toss the carrots with oil and salt and place on a baking sheet in an even layer. Roast until tender, about 10 minutes.

Thoroughly drain, rinse and dry the chickpeas. Toss them with oil and salt and spread on another baking sheet in an even layer. Bake for 5-10 minutes until the chickpeas are crispy but still tender inside.

While the carrots and chickpeas are in the oven, make the dukkah. Lightly toast the sunflower, fennel and sesame seeds in a sauté pan with no oil over medium heat for 3-4 minutes or until fragrant. Let them cool slightly and then coarsely grind the whole, toasted seeds together using a spice grinder, mortar and pestle or blender. Add to a bowl with cumin, coriander and salt, stir gently to mix, and set aside.

When the roasted chickpeas come out of the oven, toss them with a teaspoon of the dukkah and set aside.

Place half of the cucumbers and roasted carrots in a bowl. Toss with just enough dukkah to lightly coat.

Spread ½ cup of the cucumber yogurt on a plate and place the spiced carrots and cucumbers on top of the yogurt. Place more unseasoned cucumber and carrot on top and around the seasoned vegetables.

Garnish with ½ cup of the roasted chickpeas, peppers, radish sprouts and more dukkah and enjoy!

by Sara

by Katie

What’s in Season

EVENTS, CLASSES AND MORE

Field Fest

Sept. 6, 10 a.m.-3 p.m.

Discover something new at the Arboretum this season. In addition to 1,200 acres of gardens, collections and natural areas, the Arboretum offers a wide range of events, art exhibitions and classes so visitors can learn something new on each visit and deepen their connection with nature.

Celebrate the harvest season and Minnesota farmers at this annual familyfriendly festival held at the Farm at the Arb. The event features hands-on harvesting of sugar beets, flowers and potatoes; a beer garden and food trucks; and live entertainment and activities for all ages. This event is included with Arboretum general daily admission; advance registration is required.

• Learn directly from Minnesota food growers and producers while exploring interactive exhibits, games and hands-on activities in the KWS Family Tent

• Tour the crop plots and orchards

• Help harvest Minnesota crops, enter the beet-weighing contest, and take home a bag of American Crystal Sugar!

• Make a farm bouquet with flowers you can grow at home

• Stop by a tasting in the Myers Education Center Kitchen Classroom

Presented By

SCAN HERE to register or visit arb.umn.edu/fieldfest.

Arboretum Glass Pumpkin Patch

SCAN HERE to view all upcoming events and browse by topic at arb.umn. edu/events.

Sept. 12-13, 9:30 a.m.-4 p.m., and Sept. 14, 9:30 a.m.-3 p.m. Marvel at more than 6,500 stunning pieces of glass art, including handblown glass pumpkins, fall decor, garden art and Halloween glass created by a juried group of award-winning glass artists offering daily glass-blowing demonstrations. Presented by the Arboretum Auxiliary, this sale supports the Arboretum and the artists.

This event is included with general daily admission, but space is limited. Reserve in advance. Looking for the perfect pumpkin to add to your collection? Browse the sale early during a special sip and shop Opening Night celebration — special ticket required.

Opening Night Sept. 11, 4:30-7:30 p.m.

SCAN HERE to register or visit z.umn.edu/arbglasspumpkin

Book Sale

Oct. 3-5, 10 a.m.-4 p.m.

Shop from a wide selection of gently used books of all genres, DVDs and puzzles. This sale, organized by the Friends of the Andersen Horticultural Library, typically raises more than $15,000 in support of the library. Both cash and credit cards are accepted at the book sale.

HERE to learn more or visit arb.umn.edu/events/librarybooksale

Full Moon Hikes

Explore the Arboretum under the glow of the full moon during these special after-hours events that invite visitors to learn about astronomy and the natural world. Visitors can walk tea-light-lined trails to find the best moon-viewing spots before warming up around a bonfire and roasting a marshmallow.

Full Harvest Supermoon Hike

Sept. 6, 7:30-10:30 p.m.

Full Hunter’s Moon Hike

Oct. 5, 6:30-9:30 p.m.

SCAN HERE to reserve tickets or visit arb.umn.edu/fullmoonhikes

Winter Lights

Open select evenings Nov. 20-Dec. 31

Experience the wonder of winter at the Arboretum as you stroll through the gardens illuminated with light displays highlighting flowers, trees and the beauty of nature on a one-mile self-guided walk. Visitors, including all members, must reserve tickets for Winter Lights. Don’t miss the Opening Night Celebration and look for Special Theme Nights later in the season. Find all available dates and times and reserve tickets online.

Opening Night Celebration Nov. 20, 6-9 p.m.

DISCOVER FALL CLASSES

Celebrate the season of change at the Arboretum by learning something new. Inspiring fall classes are now open for registration. Explore topics including arts and literature, food and wine, gardening, well-being and photography. Family programs are also available to spark curiosity in our youngest learners.

Read about a few class highlights happening this season on these pages and head to the website for more!

SCAN HERE to browse the full list of available classes or visit arb.umn.edu/learn

Need help with registration?

The Education Team can help you choose the right class, give one as a gift or register by phone. Call 612-301-1210 (weekdays 9 a.m.-4 p.m.) or email arbedu@umn.edu for personalized support.

Browse a Newly Expanded Lineup of Botanical Art & Illustration Classes

Join the Arboretum’s growing community of botanical artists and learn to create scientifically accurate botanical illustrations guided by the best instructors in the area. Not sure where to begin? Start with our primer class or enroll in an introductory-level course.

SCAN HERE to learn more or visit arb.umn.edu/winterlights

SCAN HERE or visit arb.umn.edu/botanical-art.

Fine Art, Crafts & Literature Classes

Explore the beauty of the season with art classes led by the Arboretum’s talented instructors. Whether you’re honing your craft or trying something new, fall courses at the Arboretum offer the perfect setting to discover new techniques, connect with fellow creatives and draw inspiration from nature’s autumn palette.

Painting in Watercolor: Apples Oct. 16, 9:30 a.m.-4 p.m.

Painting in Acrylics: Blue Moon Nov. 19, 10 a.m.-12:30 p.m.

SCAN HERE to view upcoming classes or visit arb.umn.edu/art-classes.

Culinary Classes in the Kitchen Classroom

Expand your culinary skills and discover the joy of food and wine with Chef Beth Fisher and special guests this fall. Classes are held in the new Myers Kitchen Classroom at the Farm at the Arb and feature seasonal cooking, guest chef dinners, bakeology and more.

Arboretum Taste Makers With All New Makers!

Sept. 20 or Nov. 15, 10 a.m.-12:30 p.m.

Everything But the Turkey Nov. 8, 10 a.m.-noon

Photography Classes and Special Access

Expand your photography skills this fall with hands-on classes and guided sessions held both on the Arboretum grounds and on location. Learn from experienced photographers as they share their techniques, insights and passion for capturing the beauty of nature during this vibrant season.

Shooting the Light: Dusk to Dawn Two-Session Series: Sept. 12, 5-8 p.m. and Sept. 13, 6-9 a.m.

Photographing Fall Color Oct. 11, 9:30 a.m.-2:30 p.m.

SCAN HERE to view upcoming classes or visit arb.umn.edu/culinary

HERE to view upcoming classes or visit arb.umn.edu/photography-classes.

3675 Arboretum Drive

Chaska, Minnesota 55318-9613

Give today! Your gift supports the Arboretum's gardens, educational programs and horticultural research. Scan the QR code or visit arb.umn.edu/give to donate today.

by Jason Boudreau-Landis