Kerria japonica (L.) DC.
Family: Rosaceae
Japanese rose,  more...
[Corchorus japonicus (L.) Houtt.,  more]
Kerria japonica image
Paul Rothrock  
Shrub to 1.5 or 2 m tall Leaves: alternate, stalked, bright green above, paler with few hairs on veins beneath, 2 - 10 cm long, egg- to lance-shaped with a pointed tip, toothed. Flowers: borne terminally on lateral branches of previous year's growth, bright yellow, 3 - 4.5 cm across, with five oval petals and numerous stamens half as long as the petals. Fruit: a brownish black, dry achene. Twigs: slender, flexible, zigzag, yellowish green to bright green, shiny. Buds: greenish brown, small, usually with five visible scales. Form: a twiggy mass of upright and arching branches, forming a broad rounded outline.

Similar species: Kerria japonica is easy to distinguish from other species in the Chicago Region by its shiny green zigzag twigs and bright yellow, five-petaled flowers.

Flowering: April to May, with sporadic flowering throughout summer

Habitat and ecology: This species is introduced from Asia and rarely escapes cultivation.

Occurence in the Chicago region: non-native

Notes: The shiny green twigs of this species provide winter interest in the landscape.

Etymology: Kerria is named after William Kerr, a ninteenth century English botanist. Japonica means "from Japan."

Author: The Morton Arboretum