Understanding and preventing sweet cherry fruit cracking

Abstract

Sweet cherries grown in the Pacific Northwest are vulnerable to cracking, a problem that occurs when the surface of the fruit splits under pressure. Fruit cracking can have severe economic impact. Growers can minimize cracking by understanding its causes and the role cultural practices play. Historically, a cracking rate as low as 20–25 percent would render a crop unmarketable. With advances such as new optical sorters, it is now possible to profitably harvest a crop with a cracking rate of up to 40 percent. It is to the grower’s advantage to understand and reduce cracking. Fruit cracking has two causes: external, free-standing water on the surface of the fruit, and the plant’s internal water relations independent of water on the surface of the fruit. Some cherry scion cultivars are more crack- resistant than others due to their genetic makeup, which controls the form, composition, and thickness of the cuticle, the fruit’s outer layer of cutin and waxes.