Growth and Quality of Four Zinnia Cultivars Grown in Eastern South Dakota

Over the past two decades, interest in local specialty cut flower production in eastern South Dakota has grown, with several new flower farms being established across the region. However, there is currently no local, research-based information available to support growers in this new wave of interest. The purpose of this study was to assess the production and quality of four zinnia cultivars grown in eastern South Dakota to support local specialty cut flower growers in their operations. A randomized complete block design was used to evaluate four zinnia cultivars (Zinderella Peach, Oklahoma Ivory, Queen Red Lime, and Benary’s Giant Purple) grown in 2022 and 2023. Zinnias were started by seed in the greenhouse and transplanted into the field in early summer each season. Harvest began each year when flowers reached maturity (July), with one harvest event taking place each week until the first frost. Harvested flowers were rated as marketable or nonmarketable based on categories of stem length (≥18-inch-long, 13- to 17.99-inch-long, 8- to 12.99-inch-long, and <8-inch-long stems), as well as nonmarketable due to defects (curved stems, insect damage, and other damage). ‘Benary’s Giant Purple’ produced high numbers of marketable long stems and had the largest bloom size, whereas ‘Queen Red Lime’ and ‘Oklahoma Ivory’ produced high numbers of marketable medium-length stems and had lower amounts of insect damage. ‘Zinderella Peach’ produced the shortest and most insect-damaged stems and also produced lower numbers of curved stems compared with the other three cultivars. All four cultivars produced high numbers of marketable flowers and would be suitable choices for specialty cut flower growers in eastern South Dakota.