Proper pruning is vital to long term plant growth. When pruning any tree, start by cutting out broken, dead, or diseased branches. Next, focus on the tree’s structure, size, and shape. Focus on removing competing branches or co-dominant leaders (branches in the center of the tree fighting to be the tallest). Two competing leaders can easily serve as a breaking point as the tree matures. When pruning, make close (but not flush) and clean cuts. Minimize stubs that encourage decay and canker. If left un-pruned these areas may serve as a source of injury to the parent branch or trunk. Finally, prune with moderation, removing branches only when there is a very good reason for doing so. Heavy pruning can upset the balance between wood growth and root growth, and on fruit trees, can result in loss of crop. Follow these general pruning practices for trees, shrubs, and evergreens:
TREES
The best time for most trees is in late winter or early spring while still dormant. Maple, elm, black walnut, and birch bleed heavily when pruned in the spring. This doesn’t hurt the tree, however if concerned about sap flow wait until trees are leafed out before pruning. Fruit trees can be pruned anytime from March to early April.
SHRUBS
Spring flowering shrubs should be pruned right after flowering. Pruning early blooming shrubs late in the year will reduce plants chance of producing spring blooms. Other shrubs may be pruned while they are dormant. Avoid pruning late in the summer, as this may result in a flush of growth which may not harden off in time to prevent winter injury.
EVERGREENS
Arborvitaes, yews, and junipers are best pruned before new growth begins in early spring (April or May). A follow-up pruning can be carried out in June or early July to shape the new growth.