Pineapple growth and yield as influenced by urea spray schedules and potassium levels at three plant spacings

Abstract

Growth and yields from the plant and first ratoon crops of Smooth Cayenne pineapples were studied at 3 plant spacings in the row and under a number of fertilizer schedules involving preplanting applications of K and urea foliar sprays. A basal fertilizer containing 240 lb. K/acre appeared to satisfy the requirement of both plant and ratoon crops. A urea spray schedule which supplied 176 lb. N/acre/year maintained satisfactory plant growth from planting to the start of flowering. Maximum yields were recorded when the applied N was increased to 352 lb./acre/year after flowering. The interval between successive urea applications can be increased from 5 to 7 1/2 weeks provided the concentration of the spray is adjusted to supply the required amount of N. Close spacing within rows (9 in. between plants) retarded vegetative growth and reduced mean fruit weight in the plant crop. However, yields per acre were greater than in a 12-in. spacing, irrespective of nutrient level, because of the increased number of fruits harvested.