Shrubs, trees and perennials are peacefully dormant, slumbering away winter’s cold days until spring wakes them again.
Their sleepy state is the perfect time to give them a dose of good health — pruning to remove diseased, dying, dead, dangerous, broken, rubbing or crossing branches.
“Pruning is necessary only for the health of the plant,” said Kendahl Huber, a shrub and tree expert at Anderson Home & Garden Showplace in southeastern Virginia.
“Aesthetic pruning for personal preference is secondary after initial corrective pruning.”
Williamsburg, Va., master gardener Barb Landa agrees.
“Pruning permits better air circulation and sunlight penetration,” she said.
“Proper pruning encourages vegetative growth and can stimulate flowering and produce larger though fewer fruits.”
When you prune for good health, you open up the plant’s interior, allowing better air circulation that automatically reduces pest and disease issues, especially problems that breed in dark, moist spaces. An open interior, particularly on azaleas and boxwood, also promotes green growth inside the plant as it ages. Shearing a plant into a hedge or box or ball shape creates an outer green veneer that ultimately ends up harming the plants overall vigor, according to Virginia Cooperative Extension experts.
If you have a plant that’s too big for the space it’s in, then it’s just that — too big and should be removed — not pruned constantly — and replaced with a better-sized species. This is why horticulturists, especially master gardeners, preach the “right plant in the right place” guide that makes for a happier, better-managed landscape.
The wrong plant in the wrong place most often happens with “foundation plants” that quickly crowd a house — blocking windows and jeopardizing security, impeding air flow and potentially causing mildew problems and ruining the overall look and curb appeal of a home.
“Winter is a great time to take your tools off the shelf and give them a little TLC,” said Tish Llaneza, owner of Countryside Gardens, also in southeastern Virginia.
“Disinfecting your pruning tools is important to stop the spread of fungus and disease on plants. Using Lysol to disinfect causes the least damage to clothes and tools. Also sharpen and oil your tools to increase their life expectancy.”
Basic pruning tools needed include bypass hand pruners for small finger-sized woody stems, loppers for thumb-sized material and a pruning saw for larger branches and trunks. A fine sanding block removes sap and stain on blades, and a sharpening stone enhances their cutting power.
If you’re not sure exactly when to prune a plant, so you don’t remove desired flowers, use the universal rule of always prune after flowers are finished.
For example, if you prune azaleas now, you remove this year’s blooms, so prune them immediately when flowers are done or before July when new flower buds set for next year.
Roses are pruned according to the type you grow. Use loppers or pruning shears to cut Knock Out and groundcover varieties back to 12-15 inches above ground. Hybrid teas and other roses need more specialized pruning, leaving three to five stems and buds directed outward.
Perennials, including groundcovers, and ornamental grasses can be cleaned up March-April 1 — at the latest, before new growth emerges.
Wait to prune plants like spring-blooming azalea, rhododendrons and mountain laurel, fragrant daphne, evergreen holly, honeysuckle, winter jasmine, lilac, mahonia, forsythia, fothergilla and mockorange when they finish flowering. Prune now and you remove their upcoming flower buds.
Cut ¼ inch above the bud and parallel to the bud at a 45-degree angle.
Leave the branch collar (point where a branch joins the trunk or branch) when pruning.
Do not use pruning paint; air best heals a wound.
Remove rubbing and crossing branches.
Remove co-dominant leaders — or where a tree has more than one single main stem.
Remove dead, diseased, damaged and dangerous branches.
Remove water sprouts, which are shoots that come up from the trunk or branches.
Remove branches that cross back through the center of the tree.
Prune young trees to train them for strong growth, eliminating weak branching habits like narrow V-shaped crotches, or the fork where a main branch joins the trunk.
When you prune for health and shape, do not reduce more than one-third of a plant in a given season, recommends Allan Hull, a Virginia certified horticulturist and nursery manager at Peninsula Hardwood Mulch in Yorktown, Va.
“Pruning is an action, creating a reaction, which changes the direction or habit of a plant’s growth,” he said.
Here, he explains some of the pruning techniques you may use at home:
- Pinching: Used in perennials to induce branching, which helps increase bloom count.
- Disbudding: A method that reduces overall bud count so the plant’s energy produces fewer flowers that are bigger; it’s a process used mostly with camellias and roses, and works with crape myrtles, too.
- Structural pruning: The removal of dead, damaged, duplicate branches, stubs and nubs, suckers and waterspouts and double leaders.
- Reduction: A process used to shorten branches while retaining natural buds and reducing overall plant size.
- Rejuvenation: A very hard pruning process used on broadleafs, causing a plant to start over; it should only be done early to late spring. Larger plants take longer to recover; adding fertilizer and watering helps.
- Thinning: A method that reduces the number of branches by removing duplicate and weaker branches, improving air flow and structure.
- Shearing: The process of indiscriminately cutting both foliage and branches causing multiple forms of wounds to heal — also leads to skeletonizing plants.
“Skeletonizing a plant isn’t recommended,” Allan said.
“Each time you shear the plant, you reduce the foliage and cause less food production. Eventually you starve the plant, causing die back.
“Plants have natural forms that are beautiful and meant to be. Prune your plants so they retain those shapes, and give them room to grow and show off their natural beauty.”