Grow Guide for Boxwoods
Boxwoods are the quintessential hedge plants. They are evergreen, have small leaves, and tolerate heavy shearing and pruning. Boxwoods grow slowly, have few pests and diseases, and are ignored by deer and rabbits. In this grow guide, we will learn how to use boxwoods in the landscape to conceal a house’s foundation, for hedges (formal or informal), or simply as small, well behaved specimen shrubs. Boxwoods can be used to create formal hedges between gardens, along paths, and in geometric designs. Boxwoods are ideal for informal and mixed hedges, too. Stand alone specimen plants are popular for topiary and even bonsai.
Perfect Plants offers two kinds of boxwoods. The Japanese boxwood (Buxus microphylla var. japonica) can get 5-6 feet high with a similar spread and can be grown in USDA zones 5-9. It has small, inconspicuous flowers that are creamy white.
Wintergreen boxwood (B. microphylla var. koreana ‘Wintergreen’) is a smaller version that normally doesn’t get more than 2-4 feet tall. Wintergreen boxwood is more cold hardy than the Japanese cultivar, and can be grown in Zones 4-9. Wintergreen is better at keeping its dark green color all winter, too. The flowers of wintergreen boxwood are yellowish green, but, like the Korean variety, inconspicuous and of little interest. (Wintergreen boxwood is listed by some authorities as B. sinica var. insularis ‘Wintergreen’.
Whichever boxwood you choose, follow a few simple guidelines and you can expect success.
Boxwoods do best in dappled shade where they get full sun for a portion of the day. Too much full sun, especially in hot climates, will damage their leaves. Used as foundation plantings around the house, boxwoods would be happiest on the north side, and forced to suffer the most direct sun on the south side.
You can plant out containerized boxwoods anytime, but springtime is best. For hedges and foundation plantings, space the smaller Wintergreen boxwoods about 2-3 feet apart and the larger Korean boxwoods 3-4 feet apart. For tall hedges, place them a little farther apart; closer together for lower hedges. Dig the planting holes wider than the pots the plants came in and about the same depth. Carefully remove a plant from its nursery pot and uncoil any roots that may be wound around the root mass. Trim back roots that are unwieldy. Create a little mound in the center of the hole and place the center of the root ball on that, spreading out roots as you backfill the hole. You should leave 2-3 inches of the root mass exposed above the soil line. Water thoroughly while giving the plant a little shaking to eliminate any air pockets.
Spread a 2-4 inch layer of organic mulch over the root zones, but keep it from actually touching the trunks. Water every day or two for the first 2-3 months, until the plants are established. After that, try to get them one inch of water every week or ten days. If the leaves start turning yellow, it may be because the roots aren’t getting enough water. Boxwoods have shallow roots so don’t cultivate the ground close to the root zone and don’t plant other plants too close. Keep your boxwoods mulched.
Three to four weeks after planting, cut the boxwoods back by about a third to a half of their height to encourage bushy branching. Don’t fertilize the first season after planting, but every year after that apply a balanced, all purpose fertilizer such as 10-10-10 early in spring and again in early summer. Follow label directions.
Cut out dead, misshapen, and crossed branches as they appear. Beginning in the second growing season, you should shear your boxwoods two or three times per year. For a formal, box-shaped or contoured hedge or foundation planting, you should prune in early spring and again as necessary throughout the growing season. Don’t wait too long between prunings as this will result in some branches growing too tall and shading out lower foliage. Each year, cut new growth back by about one-third to one-half until the desired height of the hedge is reached.
When the shrubs are at the desired height, use a hedge trimmer to create the straight edges or contoured surfaces you desire. For box type hedges, you can use string between wooden stakes to mark where the trimmer should shear. Release your inner artist to control the trimmer for contoured hedges.
Shape the hedge so that it tapers from top to bottom. The hedge should be narrowest at its top, to allow sunlight to reach the bottom. If the hedge is wider at the top, or even the same width as the base, sunlight will be blocked from the lower parts, and leaves will die, leaving unsightly barren branches.