Bud initiation and optimum harvest date in Brussels sprouts

For six cultivars of Brussels sprouts (Brassica oleracea var. gemmifera) wi th a decreasing degree of earliness, or optimum harvest date, the time of b ud initiation was determined during two seasons. Fifty percent of the plant s had initiated buds between 60 and 75 days after planting (DAP) in 1994 an d between 70 and 86 DAP in 1995. The sequence of cultivars in time of bud i nitiation was the same as for the time of optimum harvest date. There appea red to be a fixed relation between the period from planting to bud initiati on and the period from planting to optimum harvest date. The time of optimu m harvest can, thus, be predicted after bud initiation. One day delay in bu d initiation delayed the optimum harvest date by 2.4 days. Factors influenc ing bud initiation are discussed. (C) 1999 Elsevier Science B.V. All rights reserved.