Japanese Boxwood Buxus microphylla var. japonica 'Borderline'

‘Borderline’ Japanese boxwood is an evergreen shrub in the Buxaceae (boxwood) family. Native to Japan, ‘Borderline’ was  founded as a branch sport by noted author of North American Azaleas, Clarence Towe, of Walhalla, SC. Buxus is the Latin name for boxwood or box tree. The common name of boxwood refers to the wood used to make carved decorative boxes. Another etymology is that boxwood describes the square stems of its young plants. 

‘Borderline’ has dark green leaves with brilliant yellow-gold margins. It does best in cool, well-drained clay or sandy soil in full sun to partial shade. Its foliage will usually remain green in winter if grown in shady areas, but the foliage will usually turn reddish if grown in full sun. Good green color usually returns quickly by mid-spring. Plants may be pruned or sheared as needed. However, this should be done after the last spring frost date, as a late frost may damage new growth. Mulch the plant’s shallow roots to keep them cool and moist, and avoid cultivating around them. Thin plants and remove dead or damaged branches annually to improve air circulation.

‘Borderline’ Japanese boxwood works well as a specimen or accent in the landscape, and it is also useful in shrub borders or foundation plantings. It is commonly used as edging and in formal hedges.

Insects, Diseases, and Other Plant Problems: This plant can be challenging to grow. Boxwood mites and leaf miners can affect stressed plants. Blight and leaf spot can also be an issue. Root rot occurs in poorly drained soil. Foliage burns in hot summer suns or harsh winter winds. 

The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common boxwood insect pests and diseases.

VIDEO Created by Elizabeth Meyer for "Trees, Shrubs and Conifers" a plant identification course offered in partnership with Longwood Gardens.

More information on Buxus microphylla var. japonica.