A cherry tree (Prunus spp.) in flower dances its way across spring to come into fruit in early summer. Knowing how and when to prune a cherry tree helps keep your fruit tree healthy and beautiful. Backyard growers often ignore pruning, not wanting to deprive the tree of some of its magic. Proper pruning, however, not only increases the tree's productivity but also improves the quality of its fruit and the number of its flowers. Appropriate trimming opens up the tree canopy to light, critical for cherry blossom development and optimal cherry set, flavor and quality.
Step 1: Prune in Late Winter or Early Spring
Prune a cherry tree in late winter or early spring when possible to minimize the risk of diseases. When buds are poised to break is the ideal moment to prune, just as the cherry blossom buds begin to swell. Pruning at this time encourages rapid healing rather than allowing wounds to remain open for an extended period of time; it also avoids winter injury. Don't prune ornamental cherries in the spring before flowering, as you will eliminate many blossoms.
Step 2: Envision Your Cherry Tree Shape
Look closely at your cherry tree before you begin pruning. Imagine the shape you want to achieve. Keep this shape in mind as you select the branches to remove and determine how much to cut from each branch.
Step 3: Remove Bad Wood
Eliminate dead, diseased and damaged wood, or what growers term the "three Ds." Use a sharp, sanitized pruning tool and remove branches flush with the underlying branch. Remove these bad sections when you notice them, not just in winter or spring, since they can spread or hurt the tree.
Step 4: Remove Poorly Positioned Branches
Inspect the tree for crossing branches that might rub together and get infected. Cut off the weaker of the two or the one more poorly placed. Eliminate upright-growing shoots with sharp branch angles. Trim back unbranched lateral growth by 25 percent to encourage side branches.
Step 5: Choose Scaffold Branches
Select permanent scaffold branches, which are the cherry tree's main side branches, if you have not already done so. Choose scaffold branches that spiral around the cherry tree's trunk, spaced 6 to 12 inches apart. Clip off competing branches, as well as limbs that start in the outer area of the canopy and cross back through the center. Retain branches that grow from the center of the canopy outward. Prune low-growing branches so they don't touch the ground.
Step 6: Use Good Pruning Habits
Adopt good pruning habits that encourage cuts to heal quickly on your cherry tree, preventing disease and insect infection. Make cuts flush with the adjacent branch without leaving stubs. Angle horizontal cuts so that water runs off the cut surface. You can use cherry "wound compounds" for aesthetic reasons, but realize that they don't promote healing.
Step 7: Limit Summer Pruning
Prune cherry trees sparingly in the summer, only pruning to eliminate upright and vigorous current growth. Remove entire shoots back to side shoots. Don't prune heavily in the summer when you do need to prune. Cherry trees store their energy in the branches and leaves during summer months, so summer pruning reduces the tree's energy supplies. Conclude summer pruning in July to minimize the potential for winter injury.
From Alaska to California, from France's Basque Country to Mexico's Pacific Coast, Teo Spengler has dug the soil, planted seeds and helped trees, flowers and veggies thrive. A professional writer and consummate gardener, Spengler has written about home and garden for Gardening Know How, San Francisco Chronicle, Gardening Guide and Go Banking Rates. She earned a BA from U.C. Santa Cruz, a law degree from U.C. Berkeley's Boalt Hall, and an MA and MFA from San Francisco State. She currently divides her life between San Francisco and southwestern France.