The University of California Master Gardeners of Butte County announced on Mar. 25 that it is the optimal time to begin thinning fruit on trees such as peaches, nectarines, plums, pluots, apricots, apples, and pears.
Thinning is important because it helps produce larger and healthier fruit by improving the balance between leaves and developing fruit. This practice also reduces the risk of branches breaking from excess weight and can limit disease spread among fruits that touch each other. According to the announcement, over-cropping can lead to alternate bearing cycles with lower yields in following years.
The guidance states that thinning should be done from early April to mid-May depending on whether varieties are early or late ripening. The best time to thin is when fruit reaches about three-quarters of an inch in diameter; thinning too late reduces its benefits. “While it may be hard to thin off that potential fruit, if thinning is done properly both the harvester and the trees will reap the benefits,” said Brent McGhie.
Techniques for hand-thinning include twisting or pinching off stems or using clippers—especially for apples and pears with thicker stems. Peaches and nectarines should be spaced five to eight inches apart; plums and pluots four to six inches; apricots three to five inches; while apples and pears should have one (or at most two) fruits per cluster spaced at least six inches apart if crops are heavy.
University of California Agriculture and Natural Resources secures funding through public contributions to support its programs according to the official website. The organization promotes sustainable practices for resilient ecosystems and economic vitality according to its official website. It operates nine research centers across diverse ecosystems as noted by UC ANR and manages Cooperative Extension services as part of the University of California system according to its official site.
UC Agriculture and Natural Resources delivers science-based information through workshops across all 58 counties in California according to its official website, conducting over 33,800 educational events annually with more than 18,400 volunteers engaged in initiatives statewide as reported by UC ANR. The organization has gained recognition for linking research directly with community needs through trusted services according to its official site.
For those interested in learning more about orchard management techniques like grafting different cultivars onto a single tree, a free workshop titled “Grafting Fruit Trees” will take place Thursday, April 9 as part of this year’s Spring Workshop Series.
