Greenhouse Production Of Potted Ornithogalum

Abstract

Ornithogalum thyrsoides and O. dubium are becoming popular as potted plants. To support the further commercialization of potted Ornithgalum, especially in the northeast United States, research was conducted to provide information for improved greenhouse production protocols. Four cultivars were used in the experiments: O. dubium 'Fire Star', 'Yellow Star', 'Orange Star 511'and O. thyrsoides 'White Star'. External factors including temperature, light, and plant growth regulator application affecting growth and flowering of Ornithogalum were evaluated. Days from planting to flowering exhibited a linear reduction with decreasing pre-plant three-week storage temperatures (from 27 to 9°C). Scape height increased while days to flower decreased with increasing storage duration at 9°C. Potted Ornithogalum grew best under 17°C to 19°C forcing temperatures. HID lighting produced compact, healthier-looking plants with shorter and stockier flower stems and darker green leaves. Long days (night interruption) promoted early flowering but resulted in spindly plants. Flurprimidol (Topflor) and paclobutrazol (Piccolo) effectively controlled plant height when applied as media drenches. A consumer preference survey indicated a higher percentage of participants preferred shorter potted Ornithgalum.