Year-round Greenhouse Production of Cut Sunflowers in the Rocky Mountain West

Abstract

The objective of this study was to determine the potential for year-round greenhouse production of specialty cut sunflowers (Helianthus annuus) in Wyoming. Over a 14-month period, we produced cut sunflowers in a nontraditional, transplant-based, potted method using natural light intensity and daylength conditions in Laramie, WY. Three cultivars of annual sunflowers, Dafna, ProCut Bicolor, and Sunbright Supreme, were grown from seeds sown at 2-week intervals starting on 16 Nov. 2011. Each planting consisted of four replications of four plants each. Seedlings were transplanted into 550-mL square plastic pots 15 days after sowing and were placed on greenhouse benches in blocks according to sow date. Flowers were cut at soil level when ray florets opened. Data collected included days to harvest and stem length for each stem. Results indicated significant cultivar by sow date interactions for days to harvest and stem lengths, indicating the importance of cultivar selection. Mean days to harvest ranged from 57 days (‘Sunbright Supreme’) to 103 days (‘ProCut Bicolor’). Mean stem lengths ranged from 43 cm (‘Dafna’) to 153 cm (‘Sunbright Supreme’). Overall, the results of this study show potential for year-round production of cut sunflowers and can help guide producers in the Rocky Mountain west to choose cultivars that best fit the needs of their business and market demand.