How to Prune
Follow these basic gardening tips when trimming trees, shrubs and vines.
Pruning shrubs, trees and vines establishes a stronger framework, improves growth, removes diseased or damaged branches, and improves color, flowering and fruit production.
The best time to prune plants that have been dormant all winter is from late winter to early spring. That’s when root growth is resuming, buds are swelling, and new stems and leaves are being generated. The plants are full of energy and ready to “bounce back” from trimming. Plus, it’s easier to see the structure of the plant, so you can decide what needs to stay and what should go.
But there are exceptions to every rule. In this case, it’s spring-flowering shrubs like lilacs and forsythias. Since these plants flower on the previous season’s growth, you shouldn’t prune them until after they bloom. Otherwise, you might eliminate next year’s springtime display.
The art of pruning is a simple three-step process:
- Use sharp clippers or loppers to cut out all dead, diseased and damaged branches.
- Remove branches that upset the plant’s symmetry and appearance.
- Finally, thin out branches that are growing too densely or crossing each other.
The best way to minimize pruning is to plant shrubs that are the right size for their location and are properly spaced. That way, you only need to prune the occasional stray growth or damaged branch.
Newly planted shrubs need little pruning. Remove only damaged and crossed branches. Delay major pruning and shaping for a year or two. Once a plant is established, your landscape style will determine your pruning schedule. Manicured shrubs need to be pruned once, twice or maybe three times a season, depending on how fast they grow. More naturally shaped plants need minimal pruning. Overgrown plants will need major attention.
Prune summer-flowering shrubs in late winter or early spring. This encourages more growth, which means more flowers for the summer garden.
Prune spring-flowering shrubs right after they flower. When you make a cut, prune above a healthy bud or where one branch joins another. Remove several of the older, larger stems rising from the ground on suckering shrubs like forsythia, red twig dogwood and spirea.
Always make cuts on a slight angle just above single buds. Make sure the bud is
pointed away from the center of the plant, in the direction you want the new growth.
Prune spring-flowering vines right after they bloom. Summer- and fall-blooming vines can be pruned anytime during the dormant season. Start pruning at planting time. Once established, slower-growing vines need minimal pruning. Just remove dead and damaged branches in spring. Vigorous vines like honeysuckle need yearly attention. Prune out extremely long branches and shorten those that are near their desired size. Aggressive vines like wisteria and bittersweet need more severe pruning. Cut these way back annually to keep them in check.
Most broadleaf evergreens are managed like other shrubs, but needled evergreens need a different approach when it comes to pruning.
Arborvitaes, yews and junipers should be pruned in early spring, before new growth begins, or in summer, after new growth has expanded. Fall pruning should be limited to areas with mild winters. When pruning by hand, make cuts to remove branches injured in winter and to help control size. Thin damaged or overcrowded stems back to the main trunk.
Spruces, firs, Douglas firs and cedars need minimal pruning. Prune above a healthy bud in spring before growth begins. Cut dead or damaged branches back to a healthy side branch or to the trunk, flush with the branch bark collar.