Mahonia is a genus of evergreen shrubs that belong to the family Berberidaceae. These shrubs naturally grow in regions of eastern Asia, Europe, and North America where the climate is cool and moist. The name of this genus was derived from Bernard McMahon, a horticulturist who discovered these plants in the early 19th century. There are 70 recorded species of these perennial shrubs.
Similarities with the genus Berberis, a group of herbaceous trees and shrubs, can be observed from these plants; however, distinctive characteristics of Mahonia are their foliage, which have medium to large holly-like leaflets that are about 6 inches (15 cm) long. Yellow to green blooms attached to short thin stalks along their stems serve as precursors to their fruit-bearing stage. These shrubs produce edible blue-violet berries that grow in clusters closely resembling grapes. The appearance of its fruits is the reason why one of the plant's more recognized species is called the Oregon grape.
Mahonia aquifolium, also known as Oregon grapes, can grow up to 6 feet (1.8 m). This perennial plant is typically grown for both its fruits and ornamental value indoors and in gardens. Its shiny prickly leaves turn a reddish-purple color in the winter, and its bright yellow flowers come to full bloom in the spring. The fruits of this species grow all year round but are most abundant during late spring, after the flowers have fully matured. Oregon grape shrubs achieve maximum growth in shaded areas with well-drained soil.
Leatherleaf Mahonia, or bealei, is a low-lying variety that is also commonly grown in gardens. It has grayish leaflets that are similar to hollies in appearance, with small fragrant yellow flowers that bloom in the winter. Unripe berries of bealei are green and eventually turn bluish black with gray blooms that are only about 0.5 inches (1.3 cm) in length. Houses around China often use these evergreens as borders or foundation plants.
Medicine has also made use of some species of Mahonia to treat simple ailments such as fever, gastritis, and liver problems. The roots can be dried and mixed in warm drinks, or they can be boiled so that its broth can be directly consumed. Some studies have indicated that berries from these plants can create a cooling effect in humans and lower body temperatures. Dried, powdered Oregon grapes can be made into syrup as an alternative herbal medicine for fever or stomach pain.