Nevin's barberry (Mahonia nevinii)

At a glance

Lifecycle: Perennial (hardy)
Exposure: Full sun
Frost limit: −12.2 °C

Cultivation

Unlike most members of the genus, this species requires a dry, perfectly drained position in full sun. Plants are not fully hardy in all parts of Britain, they probably tolerate temperatures down to about -10°c when fully dormant, though the young growth in spring can be damaged by late frosts. This species is closely allied to M. haematocarpa and M. fremontii. It hybridizes freely with other members of the genus. Grows and flowers well at the University Botanical Gardens in Oxford. A plant on a south-facing wall at Kew produced a good crop of fruit in 1999[K]. Plants are resistant to honey fungus.

Propagation

Seed - best sown as soon as it is ripe in a greenhouse. It usually germinates in the spring[K]. 'Green' seed (harvested when the embryo has fully developed but before the seed case has dried) should be sown as soon as it is harvested and germinates within 6 weeks[K]. Stored seed should be sown as soon as possible in late winter or spring. 3 weeks cold stratification will improve its germination, which should take place in 3 - 6 months at 10°c. Prick out the seedlings when they are large enough to handle and grow them on in the greenhouse for at least their first winter. Plant them out in late spring or early summer and consider giving them some protection from the cold for their next winter. Division of suckers in spring. Leaf cuttings in the autumn.

Edible uses

Fruit - raw or cooked, though on specimens we have seen fruiting in Britain the fruit is only 3mm in diameter[K].

Medicinal uses

Berberine, universally present in rhizomes of Mahonia species, has marked antibacterial effects.

Material uses

A green dye is obtained from the roots. Dark green, violet and dark blue-purple dyes are obtained from the fruit. A green dye is obtained from the leaves.