The genus Mahonia is not universally accepted. Many botanists prefer to treat it as part of Berberis - as per the Flora of N. America[
]. However, although they are very closely related (and there are some intergeneric hybrids), from the point of view of the gardener they are quite distinct genera. We are therefore following the treatment in the Flora of China[
] which treats them as distinct. There is, however, at least one major revision (of the Chinese genera) currently (2016) in preparation and we will review the position of Mahonia once we have seen that revision[
Berberis berberidifolia (P.K.Hsiao & Y.S.Wang) Laferr.
Berberis confusa (Sprague) Laferr.
Berberis ganpinensis H.LÃ©v.
Berbris eurybracteata (Fedde) Laferr.
Mahonia berberidifolia P.K.Hsiao & Y.S.Wang
Mahonia confusa Sprague
Mahonia ganpinensis (H.LÃ©v.) Fedde
Mahonia ganpinensis confusa (Sprague) C.K.Schneid.
Mahonia zemanii C.K.Schneid.
Mahonia eurybracteata is an evergreen shrub usually growing 50 - 200cm tall, occasionally reaching 400cm[
The plant is harvested from the wild for use as a food and a medicine. It is sold for medicinal use in local markets in China[
All parts of the plant contain the alkaloid berberine - this is most concentrated in the roots, stems and inner bark, and least concentrated in the fruits. In small quantities berberine has a range of effective medicinal applications but, in excess, can cause vomiting, lowered blood pressure, reduced heart rate, lethargy, and other ill-effects.
The fruit of most, if not all, members of this genus are more or less edible and can be eaten in quantity since the levels of berberine in the fruit are very low.
E. Asia - Western China in Guizhou, Hubei and Sichuan provinces.
Wet shady ravines and woods[
]. Forests, forest margins, streamsides, thickets, weedy slopes and open rocky ground; at elevations from 200 - 2,000 metres[
Mahonia eurybracteata can tolerate temperatures down to about -10Â°c[
]. The young growth in spring, however, is more sensitive and can be damaged by emperatures around 0Â°c[. Only introduced to Europe in 1980, the plant grew so well that within six years it was being distributed commercially from home-produced seedlings[
An easily grown shrub, it thrives in any good garden soil[
] including heavy clays. Prefers a semi-shaded woodland position in a damp, slightly acid to neutral humus-rich soil[
Plants are very tolerant of pruning and can be cut right back into old wood if they have outgrown their welcome[
This species is closely related to Mahonia fortunei[
]. It hybridizes freely with other members of this genus.
The flowers are very sweetly scented[
Some Berberis/Mahonia species (especially Berberis vulgaris) harbour the black stem-rust fungus (Puccinia graminis Persoon). This is a major disease of wheat and barley crops and can spread from infected barberries to the grain crop. The sale or transport of susceptible or untested species of Berberis is illegal in the United States and Canada[
]. We have no data on susceptibility for this species[
Fruit - raw or cooked. An acid but nice flavour and fairly juicy, it makes a pleasant nibble and is nice in other dishes, especially when added to muesli or porridge[
]. Unfortunately, there is relatively little flesh and a lot of seeds[
]. The blue or purplish red berry is about 5mm long[
]. The fruit ripens in early to mid spring, a time when little other fresh fruit is available in the garden[
The leaf is used in the treatment of cancer[
A decoction of the root and stem is febrifuge and odontalgic[
]. It is used in the treatment of dampness-heat dysentery, diarrhoea, jaundice, red painful swelling eyes, carbuncle, sore, rheumatic arthralgia, consumptive fever, hemoptysis, and dizziness[
The powdered root and stem are applied topically to wounds, abscesses etc[
Mahonia species have a long history of medicinal usage, with several members of the genus being commonly used in traditional medicine and also in modern herbalism. They are employed in the treatment of a wide range of conditions and have, in particular, been demonstrated to exert good efficacy in the clinical treatment of dysentery, internal and external haemorrhage, acne vulgaris and chronic pharyngitis amongst other diseases. Phytochemical research into this genus has resulted in the identification of more than 150 chemical constituents, amongst which alkaloids are predominant. The isolated compounds and crude extracts have been shown to exhibit a wide spectrum of in vitro and in vivo pharmacological effects, including antimicrobial, anti-inflammatory, hepatoprotective, antioxidant, antimutagenic and analgesic properties[
Berberine, an alkaloid that is universally present in the rhizomes and stems of Mahonia species, has been shown to have a marked antibacterial effect[
] and is also used as a bitter tonic[
]. Since it is not appreciably absorbed by the body, it can be used orally in the treatment of various enteric infections, especially bacterial dysentery[
Berberine has also shown antitumour activity[
The plant should not be used with Glycyrrhiza species (Liquorice) because this nullifies the effects of the berberine[
Seed - best sown as soon as it is ripe in a greenhouse[
]. It usually germinates in the spring[
]. '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[
]. 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 10Â°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[
]. Whilst they can be placed direct into their permanent positions, better results are achieved if they are potted up and placed in a frame until established[
Leaf cuttings in the autumn.