Gardening tips: The right time to prune shrubs
Is it OK for me to prune my shrubs and trees now? This question, among others, starts popping up with gardeners as we come to the end of winter and welcome spring. As the days get longer and sunnier, so does the itching of most gardenersí fingers to get to the outdoors and do something!
When is the right time to prune spring-, summer- and fall-flowering shrubs?
Most spring-blooming shrubs should be pruned right after they flower (within two weeks after flowering for shrubs blooming from early spring to early June). These shrubs bear flowers on buds formed the previous season. Waiting to prune them off in late fall or winter will cut off the blossom buds that developed in late summer and fall.
Spring-blooming shrubs include: Forsythia, deutzia, dogwood, fringe tree, golden currant, lilac, magnolia, mountain laurel, flowering quince, mock orange, azalea, rhododendron, climbing roses, spring-flowering spirea, snowball and weigela.
Summer- and fall-flowering shrubs bloom on current yearís wood and should be pruned in late winter or early spring while dormant. These include abelia, potentilla, butterfly bush, rose of sharon, crepe myrtle, beautyberry, summersweet and spirea. Avoid pruning in late summer-early fall, since this may force renewed growth that could get damaged or injured through freezing during winter.
Evergreen shrubs, like yews and junipers, are best pruned in late March to mid-April before new growth begins, while deciduous trees like maple should be pruned in late winter or early spring before they leaf out. On the other hand, fruit trees should be pruned in late February to early April, and grapevines should be pruned between March and early April.
What to prune?
Prune off scraggly, thin and weak-looking wood, crossing wood, dead, diseased and damaged branches, water shoots or branches that are tall and leggy or growing near the base. Also prune overgrown and neglected plants. After bloom time and once the flowers begin to fade, prune off the stems carrying the blooms in azaleas, rhododendrons and magnolias.
There should be no guilty feelings about pruning. Nature normally takes care of its own when pruning is done properly; so donít be afraid to prune. Pruning will help control the size and shape of your shrubs, as well as keep the shrubs flowering more regularly.
Anne Gachuhi, MS
Former Horticulture Specialist
Source: Guidesheet G6870, "Pruning ornamental shrubs," by Christopher J. Starbuck, Department of Horticulture, University of Missouri. Available online at: http://muextension.missouri.edu/explore/agguides/hort/g06870.htm.
(If you have horticulture questions, please contact Scott Killpack, Agronomy/Natural Resource Specialist, 636-970-3000, KillpackS@missouri.edu.)