Japanese skimmia

Skimmia japonica (Skimmia japonica Thunb.) – the type species of evergreen broad-leaved plants of the genus Skimmia in the family Rutaceae (Rutaceae). It was first described in 1783 by the Swedish naturalist Carl Peter Thunberg in his «Nova Genera Plantarum 3: 57».

The range includes Japan, China, the Himalayas, Nepal, Korea, Vietnam, Pakistan, and the Philippine Islands. It grows in forests, less commonly as an epiphyte on old Cryptomeria trees.

It is an evergreen shrub or small tree up to 7 m tall; in temperate climates it grows to 1.5 m. Grows slowly. The crown is dome-shaped, compact, and well-branched.

Leaves leathery, lanceolate, thick, oblong-lanceolate, entire, 7-10 cm long and 2-5 cm wide, dark green above and pale green beneath. Glands are clearly visible on the underside of the leaf.

Skimmia japonica. Photo by Schnobby

The plant is dioecious. Flowers small, with 4-7 pointed petals, 6-15 mm in diameter, white or ivory-colored, with a sweetish scent, arranged in dense panicles. Male plants are larger and have more showy flowers. One male individual can serve as a pollinator for six female plants. Flower buds are set in autumn. Blooms in April.

Photo by Musical Linguist

Fruits are drupes red or black in color, 6-12 mm in diameter, with a single seed. The fruits are inedible.

Cultivars: in horticulture Skimmia japonica is most often used. The most common cultivars are: "Rubella", "Magic Marlo", "Fructo Albo", "Fragrans", "Smits Spider", "Brocox King", "Brocox Rocket".

Hardiness zone: 7-8 (-15°C)

Soil: prefers moist, acidic, and well-drained soils rich in humus. Tolerant of drought and air pollution. Does not tolerate lime. For a potting mix you can use peat and loam with the addition of sand.

Repotting: repot in spring, choosing a pot appropriate to the size of the plant's rootball.

Light: requires bright, diffused light; grows in partial shade but loses its decorative appearance. Does not tolerate direct sunlight, as it can be quickly scorched.

Temperature: in summer it is preferable to place outdoors in fresh air. In winter it prefers cool conditions, with temperatures no higher than 10°C.

Humidity: does not require additional humidification.

Watering: in the spring and summer keep the root ball consistently moist. In winter water sparingly, especially when kept cool.

Pruning: pruning can be performed after flowering.

Feeding: from April to September it is recommended to fertilize the plant every 2 months with a fertilizer for indoor flowering plants or for rhododendrons.

Diseases: powdery mildew, grape oidium, chlorosis.

Pests: aphids, scale insects, spider mites, Panonychus citri

Propagation: propagated by cuttings and seeds. Seeds require cold stratification before sowing; after that they are sown in a peat-sand substrate with pH 5-5.5 and kept in a cool room. Semi-hardwood cuttings can be rooted from August to February. Before planting they are treated with rooting stimulants, planted in sand, and kept at 18-22°C.

Uses: in the conditions of Ukraine it is grown as a houseplant or container plant. It is used to decorate terraces, patios, balconies. It can be planted outdoors in the ground for the summer.