When it comes to pruning trees, the rule of thumb is usually that winter pruning is best. But when it comes to apple trees, this is not always the case. Winter pruning of apple trees can cause the trees to put their energy into a new flush of growth. This does not always lead to an abundant summer crop of apples. The best time to prune apple trees to prevent unwanted growth may actually be in the summer. Particularly for new apple trees that must be trained into their correct growth habit.
Delay pruning until after June. Pruning apple trees too soon in summer can open the tree to disease due to fire blight.
Sharpen your tools a sharpening stone by drawing it down the length of the blade. For young trees, you will use pruning shears for growth the size of a pencil. Branch loppers are best for young apple tree limbs that are smaller than 1½ inches. Use a hand saw for larger growth. Sterilize the tools by wiping them with a clean cloth soaked in a solution of 1 part bleach and 9 parts water.
Remove the weaker limb from any tree with a fork in it to establish a dominant leader for the apple tree. Remove the weaker limb on any branch that forks at a weak angle, such as one that is less than 90 degrees. Weak angled limbs are more likely to break under the weight of fruit.
Remove the weaker growth of any branches that grow too closely together. These branches can rub and break against one another.
Prune away any branches that grow inward toward the tree or cross the canopy instead of growing outward.
Cut away branches on older trees that no longer produce good fruit. You may need to use a hand saw if these limbs are greater than 6 inches in diameter.
Remove any diseased or broken limbs.