Mahonia

Mahonia Japonica

Mahonias are an evergreen form of the barberry family. These useful winter-flowering architectural shrubs will add shape and form to the shrub border, as well as colour and perfume from their flowers.

Family: Berberidaceae (Barberry family)
Botanical Name: Mahonia
Common Names: Oregon grape

Foliage: Evergreen glossy pinnate leaves. Green or blue-green, prickly spine-toothed (holly-like). Often turning purple in winter.

Flowers: Clustered racemes of fragrant yellow flowers. Usually followed by black or purple berries.

Flowering Period: Late autumn to early spring.

Soil: Moist but well-drained soil (chalk, clay, sand or loam). Acid, alkaline or neutral pH.

Conditions
: Sun or shade. Shelter from north and east winds.

Habit: Bushy, upright or low spreading (depending on variety).

Type: Shrub.

Origin: China, Asia and North and Central America.

Hardiness: Fully hardy in the UK.

Planting and Growing Mahonia

Easy to grown plant that thrives in most soils and conditions. Most forms prefer well-drained soil and dappled shade. They will tolerate both clay and chalky soil and heavy shade. Ideal for brightening up a dark corner.

The dense foliage provides good ground cover.

Taking Care of Mahonia

Feed young or heavily pruned shrubs annually (in the spring) with a balanced fertiliser. Water well until established.

Mulch with leaf-mould or organic matter every other spring.

Pruning Mahonia

Requires little pruning, other than to cut out dead branches and maintain overall shape.

Ground-cover types can be cut back hard in April.

Pests and Diseases

Can be affected by rust fungus and lime induced chlorosis on very chalky soil.

Propagating Mahonia

Propagate M. aquifolium, from rooted suckers in autumn or spring. For others take shoot tip cuttings in a cold frame in summer or layer suitable stems in spring. Species forms can also be propagated by seed sown when ripe.

Popular Varieties of Mahonia Grown in the UK

M. aquifolium, is low growing form with small yellow scented flowers in Spring followed by blue-black spherical fruits. The green leaves turn bronze/purple in winter. Makes good, dense ground cover or a low hedge. Height 600mm (2ft); spread 1.2m (4ft).

M. bealei (Beal's mahonia) is short upright species with erect flowering spikes. Height to 5ft (1.5m), spread to 8ft (2.5m).

M. japonica (the most commonly grown mahonia) is a tall erect form that produces long drooping racemes of fragrant yellow blooms, between late autumn and early spring. Height to 10ft (3m), spread to 12ft (4m).

M. × media 'Charity' forms a well shaped upright bush with long spikes of flowers in November-December. Height to 6ft (3m) or more.

M. 'Undulata' an erect evergreen shrub with bright yellow flowers in short, clustered racemes. Height and spread to 8ft (2.5m)