Cosmos Cut Flower Production in Utah Ali Harrison, Melanie Stock, Lorin Harrison, Amanda Pratt, Olive Stewart, Claudia Nischwitz, and Nick Volesky
Overview
Cosmos are one of the easiest and most productive cut flowers to grow. As a warm-season annual, blooms are prolific and continued, making cosmos a staple, cutand-come-again flower. The plants tolerate low water conditions, poor soil, and low maintenance, and perform better in fields than high tunnels. Available in shades ranging from whites and blushes to cranberry and orange, cosmos provide popular colors and airy textures for floral design work, particularly in late summer weddings and events.
Cosmos Types
The most common species for cut flowers is Cosmos bipinnatus, with ‘Cupcake’ and ‘Double Click’ as two of the most popular series (Table 1). ‘Cupcake’ produces blooms with a single row of fused petals that create a cup-like shape (similar to a poppy), and ‘Double Click’ produces more elaborate, full-double blooms (Figure 1). Others, such as ‘Afternoon White’ and ‘Rubenza’, have a single row of separate petals and resemble daisies
Figure 1. Three bloom types: cup, full double, and single.
(Figure 2), while ‘Sea Shells’ produces tubular petals that are less popular in floral design. Color options for cosmos include whites, blushes, cranberry, and orange, all of which are desirable in arrangements. With recent floral trends featuring earthier tones, soft peach varieties are now available, such as ‘Apricotta’. When purchasing seed, color and texture trends should be evaluated for the market, as well as plant height. The minimum stem length for cosmos is 14-inches in most markets. Many new varieties are intended for landscape and decorative purposes, and are too short for cut flowers. Chocolate Cosmos (C. atrosanguineus) is usually grown via tuberous roots and requires different management practices. Production recommendations for this crop will be covered in a separate fact sheet.
Figure 2. ‘Afternoon White’ at the perfect stage for harvest. Note the bloom is not yet fully open and has a claw-like shape.
Utah State University Extension | January 2024 | Peer-Reviewed Fact Sheet | CutFlower/01
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