Planting evergreens around a house's foundation is a landscaping no-brainer because they stay green and require little maintenance. However, foundation evergreens should be pruned to keep them looking good and scaled to the size of the house.

Many homeowners plant yews, junipers or arborvitae. After a few years, the plants block window views. The best time to prune evergreens is during the winter dormant season from December to March.It is recommended to not prune heavily in the spring because cuts made during the growing season will result in very dense growth on top. The dense upper growth can shade the lower foliage so much it will die.Many evergreens grow quite large. Homeowners who do not want to prune their plants every year should consider removing the evergreens entirely and planting shrubs that grow to a manageable size.An evergreen should be pruned while it still has manageable size and shape. Removing large amounts of growth on an oversize plant will weaken the plant and give it a "chopped-back" appearance.There are several pruning methods you can use.Use "heading-back" pruning for evergreens. Each longer stem should be cut back to a point well inside the plant. Each cut should be made back to an emerging branch, to prevent stubs. Branch stubs can be infected by fungi that cause plant disease.Proper pruning allows more air and light to penetrate the plant. The cuts made to an emerging branch will allow side branches to develop lower in the plant, which gives the plant denser growth but does not increase size.Heading-back pruning encourages green growth throughout the plant, while keeping the natural shape of the evergreen.Shearing pruning, or cutting all growth back to a uniform level, should be used only if a homeowner wants the plant grown into an unnatural shape. Turning a plant into a box or round shape removes the most attractive green growth.The following year, you will get very dense new growth on the outside, with very little green left inside. You can reverse the effects of shearing by thinning out interior branches while retaining the formal shape of the plant.Use pruners with blades that slice past each other to ensure a clean cut rather than pruners with a single blade that cut by pressing a sharp blade onto a flat surface. The latter type crushes the branches. A crushing cut takes longer to heal. For larger branches, use lopping shears or a sharp saw."Growing Green" is contributed by Lehigh County Extension Office Staff and Master Gardeners. Lehigh County Extension Office, 610-391-9840; Northampton County Extension Office, 610-746-1970.