Pruning promotes healthy, vigorous stem growth. This results in larger blooms. Pruning also removes dead, frost damaged and diseased wood. This all leads to a healthy growing season.
Proper pruning opens the center of the plant, promoting good air circulation which helps reduce disease occurence.
Proper pruning helps to maintain an attractive and well-balanced shape to the plant.
When to Prune
Here is a general list of plant groups with some tips on when they should be pruned.
Trees: Most hardwood trees should be pruned in winter while they are dormant. This allows you to see the branches and make cuts that will maintain the tree's natural shape. This also gives the tree a full growing season to heal. Cut branches off right above the branch collor. This is the area at the juncture of the limb and the tree. You can identify it by the whorls of wrinkled bark. Cutting just above this area rather than flat against the tree will ensure quicker healing. This area of the tree contains special anti-microbial chemicals and phenols, which help inhibit decay. If the cut is made here it's not necessary to use pruning paint, nature will take care of it.
Flowering Shrubs: The rule of thumb for pruning flowering shrubs is if it flowers after May 15th, prune it in late winter or early spring for lots of bloom in summer. Prune shrubs like forsythia, quince, and azaleas that flower before May the 15th as soon as the plant finishes flowering. This is because summer bloomers flower on new wood while spring flowering shrubs produce flower buds the previous growing season.
For the best bloom production follow the form of the plant rather than shearing it into a box or ball.The shrub will look much better in its natural shape.
Flowering Trees: Flowering trees follow the same rule as flowering shrubs. Summer bloomers like crape myrtles should be cut back in late winter, but spring flowering crabapples, redbuds, and dogwoods should be pruned immediately after they bloom.
To make pruning easier, mark the branches you want to cut with paint or a ribbon before they leaf out so you can clearly see the branch structure. When pruning time comes and the tree is fully leafed out you won't be guessing on the branch structure.
Evergreens: In general, broadleaf evergreens such as hollies and boxwoods don't require much pruning. A light pruning in spring before new growth begins and then again in summer works best. These broadleaf varieties will produce new growth where the cuts are made.
Caution should be used when pruning needle type evergreens such as pine or spruce, they don't bounce back very quickly. These types of evergreens should only be pruned to remove diseased/damaged wood. This can be done any time of the year except when temperatures are below zero.
