Prune Evergreens Now Before Summer Growth Peaks
As evergreen trees and shrubs across Kansas begin their annual spring growth flush, now is the ideal time for homeowners to inspect and prune landscape evergreens before summer arrives.
Evergreen species — including pine, spruce, fir, juniper, arborvitae, holly, boxwood, and yew — retain foliage year-round and typically hold two to three years’ worth of needles at any given time. These plants generally require less pruning than deciduous trees and shrubs, but proper timing and technique remain critical to maintaining healthy growth and appearance.
Pruning evergreen plants differs significantly from pruning many other landscape plants because most evergreens do not regenerate growth from older interior wood.
For pine trees, spring is the key pruning season. New pine growth develops once each year from terminal buds, producing soft shoots known as “candles.”
Gardeners looking to manage size and encourage denser growth are advised to trim back one-half to two-thirds of the candle length before needles fully expand. It is recommended to pinch candles by hand using careful cuts to avoid browning at the needle tips. Because pines naturally produce limited side branching, heavy pruning or shearing is discouraged.
Spruce and fir trees also produce a single flush of annual growth from branch tips. Prune branches back only to side buds or lateral branches while avoiding cuts beyond existing needles. Up to half of the new growth may be removed safely, though experts caution that lower branches on mature trees recover slowly because most vigorous growth occurs near the top canopy. Dwarf and slow-growing varieties may be especially sensitive to pruning and should be trimmed sparingly.
Junipers and arborvitae differ slightly by producing multiple growth flushes throughout the growing season, often from April through October. Selective pruning is recommended in early spring by cutting individual branches back to upward-growing side shoots. This method helps preserve a natural appearance while concealing pruning cuts. Do not cut back into older branch wood lacking needles, as those bare areas are unlikely to recover.
Although formal shearing remains common in many landscapes, the practice often damages the plant’s natural form and increases long-term maintenance demands. If shearing is necessary, at least one inch of previous growth should remain to prevent exposing interior dead zones.
Annual spring pruning is generally considered the safest and most effective approach for controlling evergreen growth. When plants are severely overgrown, replacement may be preferable to aggressive pruning.
Do not prune after mid-August, as late-season cuts can stimulate tender new growth that may not harden properly before winter temperatures arrive.
The guidance was provided through Kansas State University horticulture resources from the Department of Horticulture and Natural Resources in Manhattan, Kansas.
Krista Harding is a K-State Research and Extension horticulture agent serving the Southwind District. She can be reached at [email protected] or 620-244-3826.
K-State Research and Extension is an equal opportunity provider.