An easy to grow, trouble free hardy shrub, that provides a plethora bright yellow flowers in the spring.
Family: Rosaceae (Rose)
Botanical Name: Kerria
Common Names: Japanese rose, Jew's mantle, Jew's mallow, Japanese marigold bush, miracle marigold bush.
Foliage: Deciduous, bright green ovate leaves with toothed edges.
Flowers: Solitary, simple yellow flowers. Single or double forms are available. Often fragrant.
Flowering Period: Spring.
Soil: Moist but well-drained soil (chalk, clay, sand or loam). Any pH.
Conditions: Full sun or partial shade. Can be grown in a north, south, east or west-facing aspect, in either a sheltered or exposed location.
Habit: Bushy, suckering.
Type: Medium sized shrub.
Origin: China, Japan and Korea.
Hardiness: Hardy in most regions of the UK.
One of the easiest shrubs to grow. Plant during
mild weather between autumn and spring. Container grown
plants can be planted out at any reasonable time of
Grow in an open sunny position in any good, well drained, moderately fertile garden soil. Best grown against the protection of a sunny wall in colder areas. Kerria will tollerate light shade for part of the day.
Best planted on their own as they can be invasive in the border. Perfect for an informal garden or woodland setting.
Water thoroughly during dry weather until well established. Mulch with organic matter in spring and apply a general fertilizer suitable for shrubs.
Prune after flowering, where necessary. Young plants can be lightly trimmed and shaped. On more established plants, remove some of the older flowering stems down to ground level and thin out newer stems. Note: flowers appear on the previous year's growth.
Once established, Kerria has the tendency to spread by means of root runners/suckers, eventually forming a dense thicket. This can be managed by regularly removing the suckers in autumn/winter or by restricting the root run.
Generally pest and disease free.
Semi hardwood cuttings can be taken in late summer. Alternatively, divide off and pot-on rooted suckers in the autumn.
Kerria is a monospecific genus, as it only has one species: Kerria japonica. However, a few good cultivars are available:
Kerria japonica (the common species) is a free flowering shrub with rich yellow, buttercup-like flowers. Height and spread to 6ft (2m).
Kerria japonica 'Golden Guinea' is a new cultivar with arching stems packed with golden-yellow blooms. Height to 6.5ft (2m), spread to 8ft (2.5m). Available at Thompson and Morgan.
Kerria japonica 'Pleniflora' (bachelor's buttons) is a more vigorous form with double orange-yellow flowers. Height to 8ft (2.4m).
Kerria japonica 'Variegata' is a spreading compact form with single yellow flowers and white variegated leaves. Height to 3ft (90cm).