COLUMBIA, Mo. – Gardeners should make a pruning tour of their landscape now to touch up trees and shrubs, especially those planted in the past two years, said a University of Missouri horticulturist.
“There are several advantages to spring pruning,” said Chris Starbuck. “With no leaves, you can see what you are doing.”
With rising temperatures, cold snaps are unlikely to damage new growth. Pruning cuts heal quickly.
Pruning opens up plants to better light penetration and air circulation for more flowering and less disease. It also removes broken or crossing branches, he said.
“The more you cut off, the more shoot growth will result,” he said. “It is better to prune a little each year than a lot every five years.”
But not every plant has to be pruned each year, he added. “If you can’t think of a reason to prune, don’t do it.”
Prune summer-flowering shrubs such as abelia, beautyberry, butterfly bush, rose of Sharon, crepe myrtle and summersweet flower anytime before new growth begins in spring.
“Even though buds of many of these plants have started to grow, it is not too late to prune,” he said.
Prune hybrid teas, floribundas, grandifloras, hybrid perpetuals and polyanthas in early spring as the buds swell, but before growth has started.
Remove all dead wood by cutting at least an inch below the dead area. In some cases, entire canes may be winter-killed and should be removed.
Spring-flowering shrubs such as forsythia, deutzia, lilac, viburnum, mock orange and spirea are best pruned as blooms begin to fade, Starbuck said. “This allows you to enjoy the bloom and also get the plant ready for a repeat performance next spring.”
Start by removing dead or weak branches with pruning shears. Then use loppers or a pruning saw to thin forsythia and lilac by cutting about one-third of the oldest cane back to the ground. This forces vigorous shoots from the base of the plant and will form strong flower buds in the midsummer.
For more information, see the MU Extension guide "Pruning Ornamental Shrubs" (G6870).
Writer: Robert Thomas