Japanese Boxwood Perennials

Cultivated in Japan since at least the 14th century, Japanese boxwood (Buxus microphylla japonica) is an evergreen littleleaf boxwood (Buxus microphylla) variety notable for its stiff, upright habit. Because of the perennial's tolerance of heavy pruning, Japanese boxwood is often used as a formal hedge, foundation plant or sculptural edging for a flower bed.


  1. Japanese boxwood is a slow- to moderate-growing shrub that reaches a mature height of 4 to 6 feet, usually with a slightly narrower spread. The densely branched shrub produces 1-inch-long, light green leaves that sit in opposite pairs on green stems. The leaves may lose some of their luster in winter, turning shades of bronze or yellow. Japanese boxwood flowers in spring with small, inconspicuous yellowish-green flowers that have a distinct fragrance.


  1. Japanese boxwood varieties cultivars include "National," an especially erect variety that can grow up to 15 feet tall, "Kingsville Dwarf," a variety with leaves 1/5 inch long, and "Rubra," a yellowish-orange-leaved cultivar. "Morris Midget" is an exceptionally small variety that can easily be kept at a height of 1 foot or less with light pruning. "Morris Midget" is considered resistant to three common insect foes of boxwoods: boxwood mites, psyllids and boxwood leaf miners.


  1. Japanese boxwood grows in U.S. Department of Agriculture plant hardiness zones 6 to 11, where it will tolerate either partial or full sun. Dappled sunlight is ideal, especially in areas with hot afternoon sun. The shrub prefers a well-draining, acidic to neutral soil, though it will grow in alkaline soils. A thick layer of mulch can do wonders for the shrub, protecting its shallow roots from the sun and suppressing competitive weeds. Japanese boxwood responds well to pruning and will look its best if sheared regularly.


  1. Japanese boxwood is a tough plant that is often problem-free, though leaf spot, root rot and blight can cause damage. Avoid watering from above, as this contributes to foliage disease. Poorly draining, compacted soils encourage root rot. The shrub's leaves contain steroidal alkaloids, which can cause nausea, vomiting and dizziness if ingested. According to North Carolina State University, some people may also experience skin irritation from contact with the leaves, though the irritation is usually brief and minor.