By Debra Heleba, UVM Extension community horticulture director
This time of year, when plants are normally in their dormant stage, usually finds gardeners conducting late-winter pruning of apple and other fruit trees. However, recent warmer temperatures may have encouraged many trees to prematurely wake up, causing gardeners to ask, “Is it too late to prune?”
The answer is no, it’s not too late. In fact, waiting until the end of the winter to prune your fruit trees helps protect them from winter injury, so March is a great time to prune, even April if you’re at a higher elevation. Apple trees have several stages of bud growth that orchardists use to properly time disease and insect sprays.
Trees that have recently broken dormancy are in the “silver tip” stage when buds turn from a dark brown to a fuzzy-looking silvery gray. Home orchardists should prune their apple and pear trees in this stage, before the tips turn green, to avoid diseases such as fireblight. Delay pruning cherry, peach and plum trees until a little later, just before they bloom until about two weeks after petal fall (again to avoid diseases).
Annual pruning of tree fruit is important to the health of your home orchard. Pruning allows the building of the tree’s structure to support a heavy load of fruit later in the season and into the future. It also allows light and air flow into the tree, which are important for healthy growth and for limiting diseases.
As a general rule of thumb, aim to remove no more than one-third of the tree’s branches in any given year. Pruning is a balancing act because, with each branch you remove, you are reinvigorating the tree but are also pruning away potential fruit.
First, remove any dead, broken and diseased branches. Next, you will want to prune any branches that cross or rub together. Apple and pear trees are typically pruned to maintain a central trunk with branches radiating around the trunk, again allowing for air and light to penetrate the tree.
Remove suckers, which are the vertical shoots coming out of the ground, as well as “water sprouts,” the vertical shoots on branches.
Aim to keep branches that are angled 45 to 60 degrees from the trunk but remove downward leaning branches and those with tight angles. You also will want to remove shaded branches, those located directly underneath other branches and branches located directly across from one another.
When making a pruning cut, you need to cut the branch just beyond the collar. This is the area that looks wrinkled as it comes from the trunk. This will allow the cut to mend properly. Stubs can be an entry for disease. Painting the wound is unnecessary.
For more information, visit: go.uvm.edu/pruning.