Stems: decumbent, defusely spreading, woody at the base. Leaves: ovate or lanceolate, serrulate or entire. Flowers: in glandular hairy terminal racemes, calyx five-parted, corolla tubular, moderately bilabiate, the upper lip two-lobed, the lower lip three-lobed and bearded within. Fruit: seeds numerous, angled but not winged.
These handsome purple and pinkish flowers are an inch or more in length and form large mats of brilliant colour upon the rocks at very high elevations. The plant grows low upon the ground and has numerous short erect shoots, bearing the blossoms, which are tubular in shape and have two lips, the lower one being thickly bearded with soft white hairs. Penstemon comes from the Greek pente, "five," and stemon, "a stamen," and refers to the large fifth sterile stamen, which is simply a filament without an anther and is densely hairy like the lower lip. It is to this pert little bearded tongue, which projects far beyond the other four fertile stamens, that the flower owes its common name.
Penstemon Menziesii, or Small-leaved Beard-tongue, is a densely matted prostrate shrub with lateral leafy branches which bear erect flowering shoots two to six inches high. The leaves are small thick oval more or less dentate, most of the petioles and the flowering stems bearing several pairs of oblong leaf-like bracts. The purple corolla is tubular-funnel-form and bilabiate, the lower lip being bearded within, and the sterile filament is densely bearded.
Penstemon procerus, or Blue Beard-tongue, has smooth, slender stems and lanceolate, entire leaves. The flowers are bright blue or violet, and are set in dense verticillate clusters round the stem, and in a more or less elongated head. The calyx is glandular-hairy and deeply cleft, and the funnel-form corolla is half to three quarters of an inch in length and slightly hairy, the lower lip being bearded within.
Penstemon humilis, or Slender Beard-tongue, has numerous stems growing from a woody base. The basal leaves are spatulate or oblanceolate and short-petioled, and the upper ones are linear and sessile, also somewhat clasping, they are all entire or occasionally serrulate. The blue flowers grow in an upright, loose panicle, the corolla is tubular-funnel form and bilabiate within. The inflorescence is slightly viscid-pubescent.