A delightful deciduous shrub, cascara is the largest species of buckthorn, sometimes reaching heights of 30′ or more. In the southern part of its range, in the Klamath-Siskiyou mountains, it generally grows more shrubby, at about 8′-15′ tall. Cascara grows in various habitat types. It can be found on dry, southern exposures, but is more often found in moist canyons, mixed conifer forest, and along streams at low to mid elevations. Cascara flowers are tiny and inconspicuous, however, they are attractive to native bees and hummingbirds. Following the flowers come pea-sized red berries (drupes, actually, each containing 2-3 seeds) in the summer that mature into a deep purple or black color. The berries are prized by many species of wildlife, especially birds. Cascara is a larval host plant for the gray hairstreak and swallowtail butterfly. Cascara’s bright green leaves turn a gorgeous deep yellow in the autumn, and its bark is used medicinally as a highly effective laxative.
Frangula purshiana seed packets contain 1/2 teaspoon of seed.
Seed Germination Instructions
60-90 days cold-moist stratification. Sow in fall to late winter.