Nancy Brachey

Prune certain evergreens this month

The ups and downs of the weather this winter has been vexing. Not only have very cold temperatures diminished the camellia season so far, but they have interfered with getting things done outdoors.

We have the rest of this month to start and finish an essential late-winter task: pruning certain landscape plants before fresh spring growth starts.

I write about this a lot, partly because I see people pruning their hollies and laurels and boxwoods and other important evergreens in May and July. When that is done, the best new growth of the year – which emerged in early spring – is cut off, and that is very unfortunate. The new growth was fresh, vigorous and in perfect condition, very different from the older growth just down the stem.

When done in February, the plant is brought down to size, a major reason many homeowners choose to prune in the first place. The plant can be shaped so it grows into a more pleasing look. Even if you don’t wish to shorten the plant, removing individual wayward stems on the sides can improve its appearance.

Evergreens such as hollies, laurels, cleyeras, nandinas, boxwoods and ligustrums are important plants to consider for pruning in late winter. Some may show signs of weather damage caused this winter, or perhaps an insect problem that showed up last year.

Well-established ones, particularly hollies, ligustrums and nandinas that grow rapidly, can take a lot of pruning. That may be necessary to bring the plants down to a size where they do not interfere with windows, walks and driveways. These mature plants possess very well-developed root systems that will push out new growth, especially in spring.

Homeowners have asked me if they can severely cut back a large holly that outgrew its space. They fear killing it with pruning saw and shears, but cutting it back will not kill it.

The standard rule for serious pruning is one-third or less of the plant. If this does not bring it to the desired size, schedule a second pruning next February.

Exceptions exist to the late-winter pruning fest. Early-flowering shrubs such as azaleas, camellias, rhododendrons, spiraea, forsythia, pieris, gardenias and daphne should be left alone until after their blooming season.

Most landscape shrubs should be pruned by cutting out individual stems in a process called thinning. This means you select a stem and cut it off where it meets another one down below. By choosing the tallest stems for thinning, you reduce the height of the plant. Nandinas are slightly different. The tallest stems can be cut back to the base of the plant. This makes space for fresh, new growth and a better-looking plant.