When to Prune

• Pruning in the early spring before the apple tree puts out blossoms helps prevent the tree from losing growth and flowers due to the trimming. Avoid pruning branches that are already producing growth to avoid damaging seasonal flowers, which will later be apples. Trim apple trees after the last frost of the season to keep frost or late snows from harming the cut branches on the apple tree, which can limit new seasonal growth.
  
  

What to Trim

• Trim branches that have died, broken or shown signs of disease during the previous growing season. These branches are sites of weakness on the apple tree that can lead to severe disease problems, pest infestations and weaker growth during the spring, summer and fall. Dead and damaged branches are hosts for fungi and pests, and are unable to produce new growth or apples. Trim these branches back to their juncture with the tree or closest branch.
  
  

Maintenance Pruning

• Maintenance pruning is necessary if the tree suffers damage during the growing season. This can be a result of pests, storm damage or disease that weakens, breaks or kills a branch. Removing these branches during the growing season stops them from weakening the apple tree further and does not allow them to become hosts for further problems. Prune damaged branches as soon after the damage as possible.
  
  

What to Use

• There are a variety of trimming tools that are useful for pruning apple trees. Use basic pruning shears for removing smaller branches, as for thinning out the canopy. A handsaw or pole saw may be necessary for larger branches and branches that are higher off the ground, according to the University of Minnesota Extension website. When pruning for disease control, clean tools between each cut to prevent spreading disease to other portions of the apple tree.