EFFECTS OF PLANT SPACING ON UNIFORMITY IN BROCCOLI FOR ONCE-OVER HARVEST

A substantial increase in broccoli (Brassica oleracea var. italica) production in Denmark will require mechanical harvest of the crop because of the high costs of manual labour. Mechanical harvest in Denmark is assumed to be done by once-over harvest, where methods are being developed. For once-over harvest of the crop a high degree of uniformity is necessary. The objective of this work was to determine the effects of plant spacings on uniformity in maturity and head characteristics in a once-over harvested crop. The effects of plant spacings between 5 and 20 plants m-2 were investigated in three broccoli cultivars. High uniformity in maturity was found in all the tested plant spacings when the broccoli crop was harvested at the optimum stage of development. By increasing plant density the uniformity in head weight, head diameter, and floret length were reduced. It was concluded that by once-over harvest of broccoli sufficient uniformity could be achieved to make the harvest method attractive for further development of the broccoli production in Denmark.