Influence of Time of Summer Pruning and Limb Orientation on Yield, Fruit Size, and Quality of Vigorous ‘Delicious’ Apple Trees

Abstract

Abstract Vigorous, 5-year-old trees of apple [Malus domestica Borkh. cv. Red Prince Delicious/Malling (M) 9] were unpruned or pruned on July 3, August 3, or September 3 in 1979 and 1980. July and August pruning maintained number of fruit/tree and July pruning increased the number of fruit borne in the canopy interior compared to the unpruned control. September pruning decreased fruit numbers compared to July and unpruned trees. July and August but not September pruning reduced cork spot. Pruning reduced fruit size, soluble solids, and watercore but did not affect fruit color or flesh firmness. Limb orientation had no effect on fruit number, soluble solids, or watercore, but fruit on vertical limbs were better-colored and smaller than those on horizontal limbs. Spur-borne fruit in the canopy interior were larger, but less colored, compared to fruit on horizontal and vertical limbs located near the canopy periphery.