Summer Tree Pruning

Summer tree pruning is not the best time to prune, but it can be done safely.

Pruning fruit trees in the summer is actually desirable.  Here are some reasons why it is okay to prune trees in the summer:

Summer pruning is also a technique to train young fruit trees

Summer pruning is also a technique to train young fruit trees

Fruit tree health is determined by size

Summer pruning fruit trees in particular controls growth on a tree by removing water sprouts. Water sprouts are those shooters that grow straight up on a major limb. Summer is also a good time to remove the upper branches that can shade fruit on lower branches.  Opening up the canopy allows better air flow through the tree, promoting rapid drying that minimizes disease and allows better penetration of pesticides. The light penetration also promotes the growth of flower buds that will help grow fruit in the next year’s growing season.

Winter pruning is meant to stimulate the growth of the tree. Summer tree pruning is done with a different type of cut, where the branch is cut off at its point of attachment (thinning cut) to the tree and these cuts do not encourage new growth.

Summer pruning is also a technique to train young fruit trees, with thinning cuts to build your ideal tree limb structure. If you want to keep your mature fruit trees at height that is easy to harvest, summer pruning is essential. You can summer prune from eight months after blooming until mid August. Overall, summer pruning will slow the growth of a tree by reducing its root growth, helping keep dwarf trees a manageable size. Also, defective limbs can be seen more easily, or limbs that hang down too far under the weight of the leaves.

Insects

Pest control can be a benefit of summer pruning.  We will always remove fruit with damage from mites or aphids. If you do it yourself, dispose of the fruit and branches quickly, and don’t compost them.

How much to prune

Some fruit trees like peach and nectarine trees grow very quickly and should have 50% of their new growth removed after the fruit harvest. Apricots and plums grow more slowly and only need to have 20% of their new growth pruned away. Cherry trees are a little trickier.  We recommend pruning 10% off mature cherry trees in the summer.

Pruning other types of trees

Some trees in Louisville like birch, dogwood, elm, honey locust, maple, and walnut produce excessive sap from the wound when pruned in late winter or early spring. Sap flow by the way does not hurt the tree. Prune these trees in late spring or summer to minimize sap flow.

Homeowners in Louisville will also often thin trees to try to improve the grass growth below. This flat out doesn’t work and the effect is temporary because the tree growth is so rapid and the trees will quickly regrow to their original densities. The best idea we have heard for grass health under trees is converting to more shade-tolerant grass species.

Pruning evergreen trees and shrubs in the summer doesn’t affect their rate of growth very much because they actually store food in the leaves or needles, so stored food and buds are reduced about equally. Twigs and branches on evergreens can be removed any time of year with the same results. However, shaping and shearing the tips is best done just before or after their spring flush of new growth, so the new growth can hide the cuts. Shearing evergreens in the summer will produce brown cut ends that will show until the new growth the following spring.