MAHONIA. North and Central America, Asia. Certain botanists tell us these all properly belong in Berberis. However, they are almost universally known by their older name, which may yet rise again. These are rugged evergreen shrubs, often creeping by underground rhizomes to form broad colonies. All have leathery leaves divided lengthwise into pairs of toothed or spiny leaflets. They bear clusters of yellow flowers which develop into decorative, usually dark blue berries, often showing a waxy “bloom” like real grapes.
Most mahonias prefer full sun near the coast, light shade inland, reasonably well drained soil, and moderate to little watering when established. Watch for and control the small loopers (a type of caterpillar) which attack and skeletonize the leaves. Hardiness varies.
aquifolium. Oregon grape. The best known of the group, these are 3-6’ shrubs native to California and Oregon. The stems are lined by large, shiny, dark green leaves, usually bronzy in new growth. Many 3" sprays of flowers are clustered at the shoot tips in spring, forming sweet, edible berries in summer. We grow the typical form from seed. ‘Compacta’ is a dwarf selection, clumping profusely and seldom over 3’ tall. It has tightly packed leaves and typical flower clusters. 0oF. or below.
nervosa. Longleaf mahonia. A forest native, quite distinct from other mahonias. It grows slowly, eventually making loose colonies of solitary stems, each usually 1’ or less high. The leaves can be 1’ long or more and made up of up to 20 satiny, deep green leaflets. These take on a beautiful purple cast in winter. The bright yellow flowers are borne in erect sprays up to 8" long. Berries are of the usual “mahonia blue”. This is definitely one for shady nooks, performing better near the coast and in the mountains than in areas with hot, dry summers. Otherwise it is trouble-free.
repens. A mountain dweller, ranging widely over the western U.S. It is creeping in habit, producing erect shoots usually 1-2’ tall at intervals along the rhizomes. The leaves are relatively short, with broad leaflets of dark bluish green. In winter they are brilliantly plum-colored. Flowers and berries are carried in short clusters. Below 0oF.