The 2009 ASHS Annual Conference

Preharvest temperature and light conditions are thought to alter postharvest vaselife of cut flowers.  Cut Lilium ‘Dazzle’ (L.A. type) and Helianthus ‘Sunbright’ were grown in a 3 × 2 factorial at 10, 15, or 20° C night temperature and high or low light.  In additional treatments, plants were moved from a starting environment to a finishing environment two weeks prior to harvest : 1. plants started at 15° C in high light were moved to low light and vice versa, 2. plants started in low light at 10 or 20° C were moved to high light at 20 or 10° C, respectively, and 3. plants started in high light at 10 or 20° C were moved to the opposite temperature at high or low light.  Night temperatures of 20° C decreased vaselife of cut Lilium to 11.0 days compared to 13.9 or 13.1 days, for 10 and 15° C, respectively.  Similar results were obtained when plants that were moved two weeks prior to harvest were grouped with plants remaining in their starting environment.  However, when plants that were moved were grouped with plants from their finishing environment for analysis, vaselife was 13.0, 12.8, and 12.1 days for 10, 15, and 20° C, and only 10 and 20° C were different.  Thus, starting temperature may be more important than finishing temperature in determining vaselife in Lilium.  Light had no effect on vaselife of cut Lilium; however, the number of marketable stems with at least three buds at harvest was reduced by low light as well as by high temperature.  For Helianthus, there was a temperature by light interaction where vaselife decreased from 14.8 days for stems grown in low light at 15° C night temperature to 10.2 days for those grown in low light at 20° C night temperatures.  For Helianthus, it is not clear whether starting environment or finishing environment is more important in determining vaselife.