Most of us who grow fruit trees think of pruning as a winter practice, done when the tree is dormant and leafless, and the tree skeleton can be better observed.  Although dormant pruning is called for on most deciduous fruit trees, some additional summer pruning may help you maintain the tree size that you want in your backyard. Unlike dormant pruning, cutting off actively growing shoots and leaves in the spring and summer has a devigorating effect on the tree and will help control its size.  

The Fruit Bush system, a method of pruning that keeps standard-size trees or trees on dwarfing rootstock small, relies on periodic summer pruning.  The first pruning is done in late April or May when half of the new growth from that season is removed.  A second similar pruning is done in June, and if vigorous growth continues, a third pruning is done in late July or early August. 

This type of pruning results in a tree that is bushy in appearance, with a dense interior canopy that requires additional pruning so that sunlight can reach the lower fruiting branches. However, it is important to leave enough foliage to protect the tree from sunburn.

Fruit bushes are often kept at a height that allows you to do all your tree care - pruning, thinning, netting, picking, spraying - without using a ladder.  With the use of this pruning system, trees can be planted much closer together, allowing you to plant more fruit trees in a small space.  For more information on the fruit bush system go to https://anrcatalog.ucanr.edu/pdf/8057.pdf .  Fruit Trees: Training and Pruning Deciduous Trees.

Summer pruning is particularly recommended for apricots, to avoid a common branch-killing disease called Eutypa dieback, which can develop on pruning wounds that are made during wet weather.  Try to do all your pruning on apricot trees in July or August.  If some dormant pruning is still needed, wait until late in the dormant season. 

For more information on summer pruning, as well as other summer tasks in the home orchard go to https://ucanr.edu/sites/ucmgplacer/files/171595.pdf for a two page publication Summer Care of Fruit Trees by Master Gardener Mike Kluk.  Another free publication on pruning and training fruit trees can be found at https://homeorchard.ucanr.edu/The_Big_Picture/Pruning_&_Training .