Common Name: Japanese boxwood
Type: Broadleaf evergreen
Zone: 5 to 9
Height: 0.75 to 1.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: Rarely flowers
Bloom Description: Greenish yellow
Sun: Full sun to part shade
Suggested Use: Hedge
Other: Winter Interest
Tolerate: Rabbit, Deer
Best grown in evenly moist, well-drained loams (sand-clay mixture) in full sun to part shade. Plants thrive in part shade locations, including open sun-dappled conditions or light shade with several hours of morning sun or early afternoon sun. Plants can grow in close to full shade, but typically are less vigorous and more open with decreased foliage density. When grown in full sun, plant foliage is more likely to scorch, bronze in winter or suffer from mite attacks. Plants prefer soils with a pH of slightly acidic to slightly alkaline. Plants are generally tolerant of pruning and shearing as needed. Pruning should never be done prior to the last spring frost date. Pruning too early in spring often promotes tender new growth that may be damaged or killed by a late spring frost. Avoid cultivating around plants because they have shallow roots. Roots appreciate a good organic (e.g., bark or compost) mulch (1-2”). Thin plants and remove dead/damaged branches annually to improve air circulation. Boxwood is best sited in locations sheltered from strong winds with, if possible, some protection from full winter sun. Winter winds can remove moisture from leaves at a rapid rate, often resulting in dehydration and bronzing. Foliage of Japanese boxwood will usually remain green in winter if grown in shady areas, but the foliage will usually turn reddish-bronze if grown in full sun. Good green color usually returns quickly by mid-spring. Carefully remove heavy snow accumulations from plants as quickly as practicable to minimize stem/branch damage. Plants may aggressively self-seed in optimum growing conditions. Plants are easily propagated by cuttings.
Buxus microphylla var. japonica, commonly called Japanese boxwood, is a broadleaf evergreen shrub that is native to certain mountainous areas in Japan, primarily on the islands of Shikoku and Kyushu. In comparison to other species of boxwood, it is a relatively fast-growing shrub (to 12" per year) that typically matures over time in a loose upright form to 6-8' tall with a spread to as much as 16' wide. Glossy rounded leaves to 1" long are variable in shape (ovate to obovate to elliptic). When grown in sun, leaves will begin to turn orange-red-bronze after first fall frost, but they quickly return to green in spring. Axillary and terminal panicles of apetulous, pale yellow flowers bloom in March. Flowers are inconspicuous. Branchlets are sharply quadrangular.
'Morris Midget' is a low-growing, dense, compact cultivar. Slow annual growth (to 1 1/4" in height per year). Typically grown as a 10-12" tall shrub with a somewhat larger spread. If not pruned, it may eventually reach 2-2.5' tall after 25 years. Rarely flowers. Small, obovate, medium green leaves (to 1/2" long).
Boxwoods can be somewhat temperamental plants to grow in the St. Louis area where foliage tends to bronze (turn attractive brownish yellow) in harsh winters, particularly if plants are located in open areas exposed to winter winds. No serious insect or disease problems. Some susceptibility to blight and leaf spot. Root rot can also be a problem in poorly drained soils. 'Morris Midget' shows good resistance to the three main insect pests of boxwoods (boxwood leaf miner, boxwood mite and psyllids).
Small hedge or foundation plant or edger. Mass, specimen or accent. Formal gardens. Shrub borders.