Summer Pruning of Apples - Is It Worth the Time?

Apple trees have enjoyed the abundant moisture this year, with many growers commenting on the lush growth and rich leaf colour in their trees. But this extra growth can cause problems with tree crowding and fruit shading. The question is: Is it worth the time and effort to summer prune apples?

The short answer is Yes. But of course, there are several variables that will affect the tree response that comes from summer pruning.

What is summer pruning: Removal of vegetative growth when leaves and flowers or fruit are present. Only one-year growth should be removed, leaving removal of large branches and/or tree restructuring for the dormant season.

When to prune: Summer pruning is best delayed until August. By this time, the terminal buds have set, and there will be minimal regrowth or suckering this year. Remember, there may be more vegetative growth in the following year.

Why summer prune: Removal of year-old growth will open up the canopy, allowing sunlight penetration to improve fruit colour. Although this does not reduce the amount of pruning needed, August pruning will spread the workload out, when labour may be more available. August pruning also allows penetration of late season sprays, and reduces some pest problems like Wooly Apple Aphid that thrive on these shoots.

How to summer prune: After terminal buds are set, remove this year's growth in the areas around the apples. Make cuts as close to a side shoot as possible - avoid cutting only part of the shoot as this will stimulate more growth around the cut. Remove up to 1/3 to ½ of the new growth - removing too much may reduce fruit size and reduce soluble solids in the fruit.

Cautions: Avoid trees with fire blight infections, or trees weakened by pests or winter injury. Aim to finish the job by the end of August for fall apples to allow adequate time for trees to harden off. Avoid removing too much growth or fruit quality or tree problems may results. Avoid pruning if extremely hot conditions are forecast as apples may sunburn.

In general, it can be worth the time to August prune as a part of your overall pruning strategy, resulting in improved fruit color, better fruit quality, better trained trees, while allowing a better distribution of labour.

Removal of part of the current season's growth exposes the fruit for better colour and quality