
Mahonia fremontii
Mahonia fremontii
Safety & Hazards
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.
Cultivation Details
Mahonia fremontii is native to the hot and semi-arid regions of southwestern N. America and often does not grow so well in more humid climates. It can tolerate temperatures down to about -10°c[1]. Unlike most members of this genus, this species requires a dry, perfectly drained position in full sun, a gritty slightly acid soil is best[2, 3]. It grows best on a sunny south facing wall in Britain[2] and does well in a hot, dry position[1]. It requires a position sheltered from strong or cold winds[4]. Plants are slow-growing[4]. Hybridizes freely with other members of this genus[3]. The flowers are refreshingly fragrant[5]. Some named forms have been developed for their ornamental value[6]. 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[7]. This species is susceptible to infection by the fungus[7].
Propagation
Seed - best sown as soon as it is ripe in a greenhouse[8]. It usually germinates in the spring[PFAF]. '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[PFAF]. 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[8]. 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[2]. Leaf cuttings in the autumn. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Mahonia+fremontii>
Pollinators
Bees
References
- [1]Shrubs. — Phillips. R. & Rix. M. · Pan Books · 1989 · ISBN 0-330-30258-2 ↩︎Excellent photographs and a terse description of 1,900 species and cultivars.
- [2]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
- [3]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
- [4]Climbers and Wall Shrubs. — Davis. B. · Viking. · 1990 · ISBN 0-670-82929-3 ↩︎Contains information on 2,000 species and cultivars, giving details of cultivation requirements. The text is terse but informative.
- [5]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
- [6]Ornamental Shrubs, Climbers and Bamboos. — Thomas. G. S. · Murray · 1992 · ISBN 0-7195-5043-2 ↩︎Contains a wide range of plants with a brief description, mainly of their ornamental value but also usually of cultivation details and varieties.
- [7]Flora of N. America — http://flora.huh.harvard.edu/fna/ ↩︎An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
- [8]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
- [9]Berberis and Mahonia. — Ahrendt. · Journal of the Linnean Society, 57 · 1961 · ISBN - ↩︎Not for the casual reader, it lists all the known species in these two genera together with botanic descriptions and other relevant details for the botanist.
- [10]A California Flora. — Munz P.A. & Keck D.D. · University of California Press; Los Angeles · 1959 · ISBN - ↩︎An excellent flora but no pictures. Not for the casual reader.
- [11]Native American Ethnobotany — Moerman. D. · Timber Press. Oregon. · 1998 · ISBN 0-88192-453-9 ↩︎Very comprehensive but terse guide to the native uses of plants. Excellent bibliography, fully referenced to each plant, giving a pathway to further information. Not for the casual reader.
- [12]Plants for Human Consumption. — Kunkel. G. · Koeltz Scientific Books · 1984 · ISBN 3874292169 ↩︎An excellent book for the dedicated. A comprehensive listing of Latin names with a brief list of edible parts.
- [13]Medicinal Plants of the Mountain West — Moore M. · Museum of New Mexico Press; Santa Fe · 2003 · ISBN 0-89013-454-5 ↩︎Detailed information on the medicinal uses of around 150 species of plants from the Rocky Mountains of N. America. An excellent, detailed publication, written in a style that connects the writer to his readers.
- [14]The Encyclopedia of Medicinal Plants — Chevallier. A. · Dorling Kindersley. London · 1996 · ISBN 9-780751-303148 ↩︎An excellent guide to over 500 of the more well known medicinal herbs from around the world.
- [15]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
- [16]The Herb Book. — Lust. J. · Bantam books · 1983 · ISBN 0-553-23827-2 ↩︎Lots of information tightly crammed into a fairly small book.
- [17]The Dictionary of Modern Herbalism. — Mills. S. Y. ↩︎An excellent small herbal.
- [18]Encyclopaedia of Herbs and their Uses. — Bown. D. · Dorling Kindersley, London. · 1995 · ISBN 0-7513-020-31 ↩︎A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.
- [19]The Useful Plants of Great Britain. — Johnson. C. P. ↩︎Written about a hundred years ago, but still a very good guide to the useful plants of Britain.
- [20]The medicinal uses of the genus Mahonia in traditional Chinese medicine: An ethnopharmacological, phytochemical and — Jian-Ming He, Qing Mu · 2016 · http://dx.doi.org/10.1016/j.jep.2015.09.013 · ISBN 0378-8741 ↩︎A review of the medicinal uses of the genus Mahonia in China.
- [21]Medicinal Plants of China — Duke. J. A. and Ayensu. E. S. · Reference Publications, Inc. · 1985 · ISBN 0-917256-20-4 ↩︎Details of over 1,200 medicinal plants of China and brief details of their uses. Often includes an analysis, or at least a list of constituents. Heavy going if you are not into the subject.
- [22]Earth Medicine, Earth Food. — Weiner. M. A. · Ballantine Books · 1980 · ISBN 0-449-90589-6 ↩︎A nice book to read though it is difficult to look up individual plants since the book is divided into separate sections dealing with the different medicinal uses plus a section on edible plants. Common names are used instead of botanical.
- [PFAF]Plants for a Future — pfaf.org ↩︎