Pruning Calls for Precision, Depending on the Plant

Evergreen plants require less pruning than deciduous plants, but they do need some. Certain pruning techniques can help make evergreens grow more densely and keep the plants from growing too large.

Let’s assume you have a narrow-leaf evergreen--a conifer--that needs drastic pruning. Before beginning, you must know what kind of conifer you have. Pines, firs and spruces never produce new growth from leafless wood, so any pruning on these species must be only as far back into the plant as there are leaves. Otherwise you’ll be left with a leafless stub.

Thuja, juniper, hemlock and yew are conifers that can resprout new branches from older portions of wood that no longer carry leaves. Therefore, regrowth can be expected even when these plants are cut back severely.

If your objective in pruning is to make growth more dense, again consider what kind of conifer you have. Prune pines, spruces and firs while their shoots are still expanding in spring, but before needles unfurl. Snap new shoots in half by hand, which awakens dormant buds at the base of the shoots.

To make thuja, juniper, hemlock or yew more dense, prune in spring before growth begins. For a formal appearance, shear the plants; for a natural appearance, snip off individual branches with pruning shears. Follow-up pruning in midsummer keeps plants even neater.

Cutting branches from broad-leaf evergreens, such as rhododendron and mountain laurel, should be avoided. Still, an occasional, wayward branch might be ruining the form of a plant or, after years of neglect, a plant might have crept so high that it blocks a window.

In these cases, prune right after flowering. Broad-leaved evergreens generally regrow shoots from old wood, so branches can be cut back hard if need be.