Best grown in average, medium moisture, well-drained soil in full sun to part shade. Prefers sun-dappled part shade and moist, sandy loams with a slightly acidic to slightly alkaline pH. Tolerant of pruning and shearing. 'Little Gem' is noted for requiring little pruning. Avoid cultivating around plants because they have shallow roots. Roots appreciate a good mulch (1-2 "). Thin plants and remove damaged branches annually to improve air circulation. In USDA Zones 4 and 5, this boxwood is best sited in a sheltered location which protects it in winter from strong winds and full sun. Carefully remove heavy snow accumulations as quickly as practicable to minimize stem/branch damage.
'Green Gem' is a hybrid boxwood cultivar (Buxus microphylla var. koreana x Buxus sempervirens) that is noted for its globular shape and excellent winter hardiness. It is one of several cultivars in the Sheridan Green Series developed and introduced into commerce by Sheridan Nurseries of Ontario, Canada. It is a broadleaf evergreen shrub that typically grows in a dense globe to 2' tall and as wide. Elliptic to oval, glossy dark green leaves hold their color well in winter. Flowers are inconspicuous.
Boxwoods can be somewhat temperamental plants to grow in the St. Louis area where the evergreen foliage tends to bronze (turn unattractive brownish-yellow) in harsh winters, particularly if plants are located in open areas exposed to full sun and winter winds. 'Green Gem' is noted for its resistance to winter burn. Otherwise requires little special care other than annual pruning. No serious insect or disease problems. Some susceptibility to blights and leaf spot. Root rot can also be a problem in poorly drained soils. The three main insect pests of boxwoods are boxwood leaf miner, boxwood mite and psyllids.
Shrub borders. Incorporate into a foundation planting.