Summer Pruning and Thinning

Summer Pruning and Thinning of Fruit Trees

Keep your trees to size with summer pruning. Thin the fruit crops to get high quality fruit and improve next year's harvest. Tricia shares her tips on how and when to get it done.

REASONS FOR SUMMER PRUNING FRUIT TREES

Jun 14, 2011 - Charlotte from Peaceful Valley

TREE & FRUIT HEALTH ARE AFFECTED BY TREE SIZE

Summer pruning fruit trees controls undesirable growth on a tree by removing energy-wasting water sprouts. Summer is also a good time to remove leafy upper branches that excessively shade fruit on lower branches. After the lower branches are exposed, protect them from sunburn by painting them with a 50/50 mixture of water and white latex interior paint.
Winter pruning is meant to stimulate the tree. Summer pruning uses thinning cuts (where the branch is cut off at its point of attachment, instead of part way along the branch) and these cuts do not encourage new growth. By removing leaves with the limbs, the tree is also getting less energy.
Summer pruning is 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 an easy-to-harvest height, summer pruning is essential.

INSECTS

Pest control can be a benefit of summer pruning too. If you prune off fruit with damage from codling moths, mites or aphids, be careful with your orchard sanitation. Dispose of the fruit and branches promptly, and don’t compost them.

SPECIAL CASES: APRICOT & CHERRY TREES

Experts advise pruning apricots and cherries only in the summer. They are susceptible to Eutypa dieback, a branch-killing disease, if pruned during rainy weather. With this in mind, the most cautious gardeners do no dormant pruning on apricot and cherry trees. The University of California authorities in The Home Orchard say, “[I]t is best to prune apricot and cherry trees in the summer (July or August) so that at least 6 weeks of rain-free weather are likely to follow the pruning.”

HOW MUCH TO PRUNE

Some stone fruits (peaches and nectarines) grow quite rapidly and should have 50% of their new growth removed after harvest.
Apricots and plums grow more slowly and only need to have 20% of their new growth pruned away.
Experts differ on summer pruning of cherry trees. Mario Moratorio, former Farm Advisor in El Dorado County, suggested summer pruning cherry trees only for the first five years. Chuck Ingels, Sacramento County’s Farm Advisor, recommends pruning 10% off mature cherry trees.

THE MUST-HAVE BOOK

Do you have fruit trees on your property? If so, we hope you have The Home Orchard on your bookshelf. This primer from the University of California, Agriculture and Natural Resources is as essential as sharp loppers and pruners. With all those tools in hand you can become an expert at summer pruning fruit trees.