General: Figwort Family (Scrophulariaceae). Penstemon or beardtongue species are perennial forbs or sub-shrubs to shrubs with attractive flowers. They are short to long-lived. Penstemons have opposite, entire, or toothed leaves. They have several stalked flowers or flower clusters that are borne in the axils of the upper leaves or leaflike bracts. The tubular corolla is strongly to distinctly two-lipped at the mouth with a two-lobed upper lip and a three-lobed lower lip. There are 4 anther-bearing (fertile) stamens and a single sterile stamen or staminodia that is often hairy at the tip. The fruit is a many-seeded capsule.

Palmer’s penstemon is a perennial herb to a slightly woody subshrub 5 to 14 dm tall with a thick crown. The plant is glabrous and glaucous with fleshy leaves. The leaves are dentate with the upper ones sometimes triangular. The flowers range from white to lavender-pink. Cronquist et al. (1984) recognizes three varieties and provides a key to these.