Texas Mahonia, Texas barberry
Mahonia swaseyi
Family: Berberidaceae
What it is like
Mahonia swaseyi is an evergreen Shrub growing to 2.5 m (8ft 2in). See above for USDA hardiness. It is hardy to UK zone 8. It is in leaf all year, in flower from April to May. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil.
Height (m): 2.5
Where it is found
Besides rocky streams in Texas. Endemic to the Edwards Plateau in Texas, where it grows on limestone ridges and canyons at elevations of 150-600 metres.
South-western N. America.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 3
Fruit - raw but more usually cooked in preserves. Pleasantly acid, it can also be dried and used as raisins. Unfortunately, there is relatively little flesh and a lot of seeds. The fruit, which can be dry or juicy, is up to 15mm in diameter. The roasted seed is a coffee substitute.
Coffee: the various substitutes that can be used instead of coffee.
Medicine
Rating: 2
Berberine, universally present in rhizomes of Mahonia species, has marked antibacterial effects and is used as a bitter tonic. Since it is not appreciably absorbed by the body, it is used orally in the treatment of various enteric infections, especially bacterial dysentery. It should not be used with Glycyrrhiza species (Liquorice) because this nullifies the effects of the berberine. Berberine has also shown antitumour activity. The root and root bark are best harvested in the autumn.
Antibacterial: Kills bacteria.
Antitumor: Preventing, or effective against, tumors, it is used in the treatment of cancer. Probably synonymous with Cytotoxic.
Dysentery: Used in treating dysentery - an infection of the intestines that causes diarrhoea containing blood or mucus.
Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.
Other
Rating:
Attracts Wildlife: Plants noted for attracting wildlife
How it is grown
Unlike most members of the genus, this species requires a dry, perfectly drained position in full sun, a gritty slightly acid soil is best. It does well in a hot, dry position and grows best on a sunny south facing wall. It requires as sunny a position as possible. This species is not hardy in the colder areas of the country, it tolerates temperatures down to between -5 and -10°c. This plant has been recommended for improvement by selection and breeding as an edible fruit. Closely related to M. haematocarpa, differing mainly in having broadly ovate bracts up to 8mm long. It is also closely related to M. nevinii.
Propagating it: 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 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. 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.
Best place to grow: Woodland Garden Sunny Edge; Dappled Shade;
Habit: Shrub
Hardiness: 7-10
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: No shade
Moisture: Dry, moist