What pruning mistakes cause permanent damage?

Mistakes in pruning usually arise from a short-coursed feeling of urgency or dull blade. I recall a time when I witnessed my neighbor's apricot tree die after drastic summer pruning. The sap attracted borers, and the tree's health faded out. There are three primary mistakes that will ruin your tree no matter the caring aspects of the pruning: removing the collar of a limb, too much thinning, and cutting in the wrong season. Recognize these problems with any tree before grabbing your shears.

Recovering from injury requires patience from both you and your tree. For all flush-cut wounds, I apply a few thin layers of wax only in the fire blight zone. There was an over-pruned apple at my client that came back strong after three years of trimming every year at 10%. Do not fertilize the trees that have been stressed, added nitrogen pushes luxuriant leafy growth rather than fruiting wood.

I guide my apprentices with the 20-30-50 rule, which means, 20 percent is deadwood removal, 30 percent is thinning cuts, and 50 percent is structural planning. A Michigan cherry farm stopped 10 years of decline by putting it on paper first, and I encourage you to sketch your cuts. It eliminates over-reactive over-pruning cuts.

Read the full article: How to Prune Fruit Trees: A Step-by-Step Guide