Buxus microphylla var. japonica 'Borderline'
- Common Name(s):
- 'Borderline' Boxwood, Japanese box, Littleleaf box
Madonna may loathe hydrangeas, but this plant should push her over the borderline for boxwoods! Found as a branch sport by our friend and noted author of North American Azaleas, Clarence Towe, of Walhalla, SC. ‘Borderline’ has dark green leaves with brilliant yellow/gold margins. No patent or trademark.
The common name of boxwood is in reference to the prior use of the wood to make carved decorative boxes. Another etymology is that boxwood describes the quadrangular (square box cross section) stems of young plants. It 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.
Foliage of Japanese boxwood 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. 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 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. Growth rate: Slow
Seasons of interest: Year-round evergreen shrub with nice form.
Wildlife Value: Deer- and rabbit-resistant. Flowers may be insignificant to a human's eye, but bees find them eye-catching.
Insects, Diseases and Other Problems: Plants are susceptible to boxwood leaf miner and boxwood mites, but are usually not affected by boxwood psyllid. Japanese boxwood is considered to have good resistance to nematodes. Boxwoods have susceptibility to blights (e.g., Boxwood blight, Cylindrocladium buxicola) and leaf spot. Root rot (Phytophthera) can also be a problem in poorly-drained soils.
- 6-8 ft
- Dark green leaves with brilliant yellow/gold margins. Small (0.39–0.98 in), opposite, simple leaves, broadest above the middle with a rounded or notched tip.
- Insignificant greenish-cream flowers, in axillary clusters, 4-parted. Fruit n/a.
- Broadleaf evergreen
- 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, become bronzed in winter, or suffer from mite attacks. Plants prefer soils with a pH of slightly acidic to slightly alkaline. Boxwood is best suited 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.
- Medium to fine
- 10-15 ft
NCCES plant id: 3130