Harvesting too early results in fruit that is off-flavor, poorly colored, small, and subject to bitter pit and storage scald. Leaving fruit on the tree too long often results in the development of watercore and a shorter storage life. Early tree training, annual pruning, proper fertilization, and sound pest management can greatly affect tree vigor and, thus, fruit condition. Light crops, crops from extended bloom periods, or crops with high nitrogen levels may differ markedly in maturity date and subsequent storage potential. Each block and cultivar or strain should be evaluated separately for its maturity and storage potential.
Growers can use several measurements to pinpoint optimum harvest time.
Before doing any measurements, collect a good representative sample of fruit. Choose five to eight trees per block per cultivar and rootstock that are typical of the trees in the block, and carefully mark them so that you can collect weekly samples. Trees should have a uniform crop load and be of uniform vigor. Begin sampling approximately 4 to 5 weeks before normal harvest is anticipated. Sample four fruits from the periphery of each tree, selecting fruit that is free of any visible insect injury or disease damage.