Penstemon cardwellii

Cardwell's penstemon

Habit: this penstemon has woody stems which grow 4-12 inches long and spread by layering, sometimes forming thick mats. Its opposite, basal leaves are attached to stems with short petioles (leafstalks) and are elliptic to oblong, measuring about 1 inch in length. Leaf margins can be either entire or irregularly serrated. Flowering stems grow 4-8 inches long and have smaller but broader leaves which lack petioles. Inflorescence is sparsely glandular and composed of a compact raceme. The flowers are few and only 1.5 inches long, but appear larger in relation to the minuscule size of the leaves and stems. The showy blue-violet to purple corolla is shaped as a tube and bears a wide, lobed mouth, from where long woolly anthers are projected outward. The flowers bloom from May to early August and sometimes again in the fall.

Ecology: found in volcanic pumice rock slopes, open woods or forest edges at moderate elevations. It is a native species of the Oregon Coastal Range and the Cascade Mountains, occurring from central Washington through Oregon. A large community has settled on volcanic rubble around Mount St. Helens, in the aftermath of the 1980 eruption.

Growing conditions: full sun to light shade, and well-drained, moist to dry soils. The intense violet color of the flowers is perfect to brighten a partially shaded rock garden or dry bank. It looks beautiful year-round, even when not flowering.

This species was named in honor of Dr. James R. Cardwell, a horticulturist, author and the first dentist to practice in Portland, OR. Cardwell emigrated to Oregon by wagon in 1851 dreaming of establishing a nursery in the west. His wagon tipped over when crossing the Snake River and he lost his cargo, including the precious nursery trees and plants he was taking with him. Heartbroken, he continued his dentist practice in Portland, and with time fulfilled his dreams in the horticulture business. During his lifetime, he actively contributed to the study of plant sciences in the new state.


Herbaceous Perennial
4-12 inches (10-30 cm)
12-15 inches (30-38 cm)
USDA Zones:
5b to 9b

Native Habitat

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