Mahonia, Fremont's mahonia

Mahonia fremontii

Physical Characteristics

Mahonia fremontii is an evergreen Shrub growing to 2.5 m (8ft) by 2 m (6ft) at a slow rate. 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, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: neutral and basic (mildly alkaline) soils and can grow in very alkaline soils. It cannot grow in the shade. It prefers dry or moist soil and can tolerate drought.

Distribution

South-western N. America.

Habitats

Woodland Garden Sunny Edge; Dappled Shade;

Edible Uses

Edible Parts: Fruit Edible Uses: Fruit - raw or cooked[257]. It is usually cooked[177]. An acid flavour but it is rather nice raw, especially when added to muesli or porridge[K]. Unfortunately, there is relatively little flesh and a lot of seeds[K]. A beverage has been made from the fruit[257]. The ovoid fruit is about 15mm long[200]. All varieties produce edible fruits, although quality varies. The moist-fruited form offers sweet, grape-strawberry flavor with mild acidity and minimal bitterness, while the dry-fruited form yields papery, tart berries with little flesh. In both cases, the berries are highly seedy, but edible raw or cooked. Edibility rating: 4 / 5) for moist-fruited forms; (2 / 5) for dry-fruited forms. Taste, Processing & Kitchen Notes: Fresh, ripe berries from moist-fruited plants are juicy and sweet, with a pleasant balance of acidity reminiscent of strawberries or red grapes. The seeds are small and firm but chewable. These berries make excellent preserves, jellies, syrups, or fruit leathers. For fruit bars, it’s best to deseed by mashing and straining before drying the pulp [2-3]. Dry-fruited forms have papery skins surrounding seeds with minimal pulp. When boiled, they soften slightly, releasing a tart juice suitable for sweetened syrups. Even dry fruits yield flavorful results when simmered with sugar or honey. Because barberry fruits attract insects, always inspect for larvae before processing [2-3]. Harvest & Processing Workflow: Harvest ripe berries in mid- to late summer when fully colored and slightly soft. Clip fruit clusters with scissors to avoid damaging spiny branches. Sort and wash the berries to remove insects. Fruits can be sun-dried for fruit leathers or boiled for syrup or jelly. To make syrup, simmer berries in water for 20 minutes, strain through muslin, sweeten, and reduce to desired thickness [2-3]. Cultivar / Selection Notes: While no formal cultivars exist, horticultural selections of Fremont’s barberry emphasize fruit size, leaf color intensity, and berry abundance. Some cultivated forms used for ornamental purposes are derived from the moist-fruited populations, valued for their flavor and vivid color. Look-Alikes & Confusion Risks: May be mistaken for Red Barberry (B. haematocarpa), which has smaller, redder fruits and more numerous leaflets (5–9) with slightly narrower shape. Fremont’s barberry tends to have thicker, balloon-like fruits and leaves with a bluish cast. The two species often hybridize, creating intermediate forms. Traditional / Indigenous Use Summary: Fremont’s barberry was widely used by Native American tribes of Arizona and Utah. The berries were eaten fresh, dried, or cooked into preserves, while the roots and bark were used medicinally for stomach ailments and as a yellow dye. Some tribes pit-roasted roots for flavor or used them as a bitter tonic. The Hopi and Navajo are both known to have utilized the fruits in various forms.

Medicinal Uses

Antibacterial Antitumor Bitter Dysentery Hepatic Laxative Tonic The plant has been used as an aid for the gums[257]. The roots are bitter tonic, hepatic and laxative[257]. An infusion has been used to promote digestion[257]. Berberine, universally present in rhizomes of Mahonia species, has marked antibacterial effects[218] and is used as a bitter tonic[213]. Since it is not appreciably absorbed by the body, it is used orally in the treatment of various enteric infections, especially bacterial dysentery[218]. It should not be used with Glycyrrhiza species (Liquorice) because this nullifies the effects of the berberine[218]. Berberine has also shown antitumour activity[218]. The root and root bark are best harvested in the autumn[213].

Known Hazards

The fruits are safe to consume, but stems, bark, and roots contain berberine, a powerful alkaloid with antimicrobial and physiological effects. These parts should not be ingested or used medicinally without professional oversight. As with all Berberis species, excessive consumption may cause mild stomach upset in sensitive individuals.