Mahonia repens
Synonym: Berberis repens
Common name: Creeping Oregon grape
Mahonia repens, an evergreen shrub with a low and spreading habit, is found in the dry plateaus, conifer forests, and on foothills in western North America, in British Columbia, Alberta and in many western American states. In its natural habitat, Mahonia repens grows to about .3 metres or 12 inches in height, but can grow taller depending on the environment.
M. repens has short clusters of golden yellow flowers which are lightly fragrant. These bloom in mid-spring, attracting bumblebees and other pollinators. The flowers give way to blue berries which are in grapelike clusters. M. repens has holly-like, glossy blue-green foliage. These leaves are rounder than on other mahonias and also less prickly. They may turn bronzy purple in winter.
M. repens is a hardy plant, adaptable to a wide range of growing conditions. It can grow in full sun, partial sun, or full shade. It is not fussy about the soil in which it grows as long as it is not soggy.
M. repens is attractive to wildlife. Its flowers provide nectar for bees, butterflies, and other pollinators. The fruit is a favourite of birds and some mammals. The foliage provides some cover and browsing for many species.
Creeping Oregon grape berries are edible raw or cooked, but have a sharp, sour flavour. Their juice has natural pectin and can be made into jelly and jam. First Nations people made good use of M. repens. They ate the berries raw, sometimes mixed with salal. Both the bark and berries were used medicinally. The roots and bark were shredded to make a yellow dye.
M. repens is a good, dense groundcover. It is useful for preventing soil erosion on slopes due to its rooting and matting tendencies. It hybridizes easily with its cousins.
The genus name Mahonia was given by Thomas Nuttall to honour an Irish emigre names Bernard McMahon who settled in Philadelphia. Mr. McMahon was a nurseryman, seedsman, and a florist. In 1804, he published the first American seed catalogue, and in 1806, he wrote The American Gardener's Calendar. He also established a nursery and botanic garden in Philadelphia. Thomas Jefferson selected Mr. McMahon as one of two men to receive and grow specimens collected by the Lewis and Clark Expedition. The specific epithet repens means 'creeping' in Latin. It refers to the creeping habit of the rhizomes (underground stems).
Mahonia repens can be found in various areas of VanDusen Garden. The photos were taken of the shrubs growing in Bed 22B near the Floral Hall.
Mahonia is sometimes treated as part of the Berberis genus.
More about yellow-flowering mahonias
Text and photos by Kumi Sutcliffe, except flower photo, which is from Wikimedia.