STAMINATE AND PISTILLATE FLOWER PRODUCTION OF SUMMER SQUASH IN RESPONSE TO PLANTING DATE

Staminate and pistillate flower production in summer squash (Cucurbita pepo L.) fluctuates readily in response to the various crop production environments throughout the southeastern United States. 'Dixie', 'Senator', 'Lemondrop', 'Meigs', and 'Elite' squash were planted at various times over 2 years in Griffin, Ga., to determine the effect of planting date on staminate and pistillate flower counts for the first 2 weeks of flowering. Staminate and pistillate flower counts varied considerably depending on cultivar and time of planting, but no consistent pattern emerged. The production of staminate flowers was generally more variable than that of pistillate flowers. The pistillate : staminate flower ratio was generally stable for 'Senator' and 'Elite', but not for the other cultivars, particularly 'Dixie'. 'Dixie' produced more pistillate than staminate flowers 50% of the time, whereas 'Senator' always produced more staminate flowers. Pistillate flower production for 'Senator' and 'Elite' was restricted during hot weather. These data indicate that staminate and pistillate flower counts of squash fluctuate under varying environmental conditions and that maintaining production over a range of planting dates will depend on careful cultivar selection.