Question: I just planted a few fruit trees. When is the best time of year to prune them? Answer: The time of year that you decide to prune your trees will depend on your reasons for pruning and environmental considerations. For your tree’s first year, you should limit your pruning to removing damaged wood while the roots become established, as the more branches you leave initially, the quicker the roots can grow and recover from being transplanted to your orchard. You can begin training and shaping your tree in the first dormant season after planting. Dead and damaged wood should be removed year round, as soon as it occurs. This will help to prevent the spread of infection and secondary damage. For most situations, remove all the bad wood, but do not cut into the healthy tissue. However, you can cut into good wood if it will prevent future damage, such as removing branches that rub together. Never cut into a healthy branch collar. Diseased wood can usually be removed year round. However, there are some exceptions for trees with specific diseases, such as fire blight when you should remove an additional 8 to 12 inches of healthy-looking wood beyond the diseased area. Refer to the University of California IPM website to determine the best time of year and amount to remove on infected branches to reduce the chance of spreading the disease further.
Shaping and training is normally done in the mid to late winter, before the buds swell. At this time of year, the tree branch structure is easiest to see. Trees may “bleed” at this time from pruning wounds; if this happens on your tree, don’t worry! Oozing sap won’t harm your tree at all. Thinning is normally done in midsummer following spring leaf growth. Thinning at this time will allow light to penetrate the canopy, increase air circulation, and reduce disease. Thinning the fruit in late spring to one or two per cluster or one every 2 to 8 inches along a branch will encourage larger fruit in the current year. For trees that tend to fruit only in alternate years, fruit thinning can help to fix the problem. For all pruning on live wood, avoid trimming any branches before or during wet or humid weather, or when the tree is stressed from drought. Spring during early growth should be avoided as the cambium and bark are easily damaged at that time, and pruning at this time can stimulate the growth of undesirable water sprouts. Late summer and fall should also be avoided, as this can stimulate new growth too late in the year. Regular pruning maintenance is important to keep your trees strong and healthy. Be sure to check out our Fruit Tree Central for more articles and videos on how to prune your trees.