THE EFFECTS OF GREENHOUSE TEMPERATURE AND ANCYMIDOL CONCENTRATION ON HEIGHT AND FLOWERING TIME OF FREESIA HYBRIDA GROWN AS A CONTAINER PLANT

Freesia cultivars Aurora, Stella, and Uchida were grown as container plants at three different average greenhouse temperatures: 10, 15 and 20° C. Corms were stored dry for 5 weeks at 5°C prior to planting. Ancymidol was applied 1 week after planting as a soil drench at rates of 0, 1, 2, and 3 mg per pot A.I. Final plant height and number of days to flower were recorded. The warmest greenhouse temperature (20°C) resulted in the tallest plants among all three cultivars. Ancymidol treatments reduced plant height, but were less effective as greenhouse temperatures increased. The number of days to flower decreased with increasing greenhouse temperature, but the response varied somewhat among the varieties, with Aurora flowering more quickly at 15°C than 20°C. Ancymidol tended to delay flowering significantly only at higher greenhouse temperatures, but responses differed among varieties.