Slow growing, broad-leaved evergreen shrubs, like boxwood, have the majority of their growth from buds at or near the ends of the branches. Some develop a dense outer shell of foliage with only a few leaves in the center. Most require little pruning except when an occasional branch outgrows the general habit of the plant. Boxwood have more of a main branch framework than do other faster growing shrubs (e.g., Forsythia) that tend to sprout vigorously from the base.
Some boxwood have central leaders with tall, straight trunks such as B. sempervirens ‘Fastigiata’, ‘Pyramidalis’, and ‘Graham Blandy’. Others have several main branches with spreading crowns such as B. sempervirens >Suffruticosa= and B. microphylla var. japonica. Then there is the low mounding habit, which would include B. microphylla ‘Compacta’, ‘Green Pillow’, and B. microphylla var. japonica ‘Morris Midget’. Between these extremes, many intermediate forms occur. Proper pruning can exploit the natural characteristics of a specific cultivar as well as enhance its appearance and maintain its health. There are three different methods, each of which may be appropriate depending on the desired results: thinning, shearing, and heading-back.
