Buxus sempervirens is typically grown in evenly moist, well-drained loams (e.g., sand-clay mixture) in full sun to part shade. Plants will grow well in a variety of part shade situations, 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. 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. Foliage may bronze in winter when exposed to half day to full day sun. Winter winds can remove moisture from leaves at a rapid rate, often resulting in dehydration and bronzing. Carefully remove heavy snow accumulations as quickly as practicable to minimize stem/branch damage. Species plants are easily propagated by cuttings or seed.
Buxus sempervirens is a rounded to broad-rounded shrub or small tree that is native primarily to open woodlands and rocky hillsides in southern Europe, northern Africa and western Asia. It typically matures in a shrubby form to 5-15' tall, but may grow as a tree to as much as 20-30' tall. Small, elliptic to oval to oblong leaves (1/2" to 1 1/2" long) are simple, opposite, smooth-margined and evergreen. Leaves are dark glossy green above and yellowish-green below. Inconspicuous, apetulous flowers in axillary clusters are pale green to yellow to creamy white. Flowers appear in April and May. Fruit is a dehiscent capsule (to 1/3" long) that matures to brown.
Genus name comes from an old Latin name.
Sempervirens from Latin means always green in obvious reference to the evergreen foliage.
Common name of boxwood is in reference to the prior use of the wood to make boxes. Another theory on common name is that the name is in reference to young plant stems which are quadrangular (square box cross section).
'Vardar Valley' is a dense, compact, many-branched, broad, mounded evergreen shrub. Slow annual growth (to 1.5" per year). Typically grown as a 2-3' tall shrub with a larger spread. Apetalous, greenish yellow flowers (separate male and female flowers on the same plant) appear in spring. Flowers are sparse and insignificant, but fragrant. Small, round to obovate, medium green leaves (to 1 1/8" long) with a blue hue.
Boxwoods can be somewhat temperamental plants to grow in the St. Louis area where foliage tends to bronze (turn unattractive brownish yellow) in harsh winters, particularly if plants are located in open areas exposed to winter winds. Otherwise requires little special care other than annual pruning. Some susceptibility to blight and leaf spots. Root rot can be a problem in poorly drained soils. 'Vardar Valley' shows good resistance to two of the three main insect pests of boxwood (leaf miner and mites), but is subject to psyllid infestations in certain areas of the U.S.
Best as a hedge or foundation plant. May be massed, grouped or used as a specimen or accent. Formal gardens or shrub borders.