Summer Pruning

Summer pruning in deciduous trees the second and third seasons includes 1) removing watersprouts and suckers (small upright shoots) along the trunk and base, and 2) maintaining a single straight leader. Ideally, most deciduous trees should be pruned when dormant, but corrective shaping is essential and should be done at the first opportunity. Broken, damaged, and dead branches are best removed when observed.

Broadleaved, upright plants such as ‘Nellie R. Stevens’ and ‘Fosters #2’ hollies need attention throughout the summer months. The terminals should be tip-pruned to increase branching density. A strong vertical terminal should be 8 to 10 inches long before being pruned. Multiple leaders will develop from this shoot; therefore, later in the season another single terminal should be selected. Evergreen trees are often sheared by removing the terminals of all lateral shoots, but a single leader is maintained.

Trees susceptible to fire blight, such as crabapple, pear, and other rosaceous species, may require extra spring and summer pruning. Tips of branches turn black as the disease moves down the branch. To control the disease, prune at buds or branches well below the discolored area. (This may be 12 to 15 inches on infected branches.) This disease is easily spread by infected pruning shears, so disinfect pruning equipment by wetting all cutting surfaces with isopropyl alcohol or another disinfectant.