Most trees and shrubs do not need to be pruned back, but if you are looking to shape a tree or to keep a larger variety of shrub a more diminutive size, here are some tips:
Spring-flowering shrubs and trees set their flower buds during the summer. If you prune back forsythia, lilacs, azaleas, pieris, or rhododendron (as well as spring blooming trees) in the fall, you will remove many of the plant’s spring flowers.
A good rule of thumb in pruning is “Prune after bloom.” Trees and shrubs should be pruned back immediately after they flower before new buds have had a chance to form. Taking cuttings to bring inside is actually a great way to prune flowering shrubs like lilacs, because it ensures that you are not pruning too late, and thus removing next year's blooms.
To keep a shrub like pieris from growing leggy, we cut off the spent blooms and any branches growing awkwardly taller than the rest.
Prune at the “Y”: When you cut back a branch, cut at a “Y” branching and don’t leave any little stump. Cut close and neat.
Look before you cut!
When pruning, Victoria pulls the branch away from the tree or shrub to examine what the plant will look like with out it. Pruning can be intimidating, but start by cutting off dead pieces first, then crossed branches. Then step back and see what it looks like!
Suckers: Unwanted suckers (new shoots) growing up from the base of a tree or shrub can be cut off at any time. For the best results, uncover them and cut the suckers 2” below the soil line.
And then feed them!
June and July are the months to fertilize spring-flowering plants to encourage new growth and the setting of next year's buds. You can use an all purpose fertilizer, like Plant-tone or for acid loving shrubs like Azaleas, Rhododendrons, Andromeda (Peiris), and Mountain Laurel, you can use Holly-tone.