Cardwell's penstemon is named for Dr. James R. Cardwell who actively studied wildflowers in Oregon in the late 1800s. It is an attractive, shrubby penstemon with many lax to matted stems from 10-30 cm long. The basal leaves range from 1.5-4 cm in length and have a short petiole. They are rounded or elliptical in shape with rounded ends and entire to toothed margins. The stem leaves are smaller in size and often sessile. The stem leaves may be rounded or pointed at the tips. All the leaves are smooth with a bright green color.
The inflorescence is a crowded, few-flowerd raceme. The calyx ranges from 7-12 mm long with the sepals lanceolate to ovate in shape, tapering to pointed tips. The tubular corolla is blue-violet to purple in color, and ranges from 2.5-3.8 cm in length and up to 1 cm wide at the mouth. The upper corolla is longitudinally ridged while the palate is 2-ridged with long hairs. The anther sacs are woolly-haired, opposite, and explanate. The short, slender staminode is found entirely in the tube and has a sparse cluster of long, yellow hairs near the tip.
Cardwell's penstemon may be successfully added to the moister west Cascades rock garden. They like some elevation and good drainage. They sprawl across the ground, rooting at nodes. The center may die after several years but the outer portions of the plant may live on for several years. I have several plants, and some were placed as stem cuttings in the moist (clay) ground at mid-winter where they have survived for a number of years. The native species as well as an albino form may be purchased from many Pacific Northwest nurseries which deal in wildflowers.
Cardwell's penstemon is found on open, often rocky slopes at middle to high elevations.
Cardwell's penstemon may be found from northern Skamania County (near Mt. St. Helens) in southern Washington south (primarily west of the Cascade crest) through the Cascades to the Klamath region in southwestern Oregon, and hence west to the Coast Range where it is found northwards to Tillamook County, OR.
In the Columbia River Gorge it may be found between the elevations of 2200'-4600' from the Upper Washougal River Road east to about Mt. Defiance in the central Gorge.