Culture:
Best grown in average, dry to medium moisture, well-drained soil in full sun. Tolerant of occasional drought and inundation once established. Can be grown in clay soils but avoid overly wet, poorly drained conditions.
Noteworthy Characteristics:
Penstemon digitalis, commonly called foxglove beardtongue or tall white beardtongue, is a clump-forming, Missouri-native perennial which typically grows 3–5′ tall and occurs in prairies, fields, wood margins, open woods and along railroad tracks. Features white, two-lipped, tubular flowers (to 1.25″ long) borne in panicles atop erect, rigid stems. Flowers bloom mid-spring to early summer and are attractive to hummingbirds, butterflies and other pollinators. Basal leaves are elliptic and stem leaves are lance-shaped to oblong.
The genus name Penstemon likely comes from the Latin *paene* meaning “almost” or “nearly” and the Greek *stemon* meaning “stamen.” The name may also come from the Greek *pente* meaning “five” and *stemon* meaning “stamen.” Both refer to the fifth, sterile stamen (staminode) that characterizes members of this genus.
The specific epithet digitalis refers to the genus *Digitalis*, members of which are often called foxgloves, and the flowers of which this species is thought to superficially resemble.
The common names of this species refer to the appearance of its flowers and growth habit. Penstemons are sometimes commonly called beardtongues because the sterile stamen (staminode) can be hairy.
Problems:
Root rot can occur in wet, poorly-drained soils. Leaf spots are occasional problems. Can spread somewhat aggressively in a garden setting. Deer tend to avoid this plant.
Garden Uses:
Mass in sunny borders, rain gardens, wild gardens, native plant gardens or naturalized areas. Excellent for fresh cut flower arrangements.
Penstemon digitalis (Foxglove Beardtongue) matures to 3′ in height and has white to pink flowers. It prefers medium to dry medium soils but can adapt to many light conditions: full sun to part shade such as clearings within forests, woods’ edges, and savannas. It is very easy to grow from seed.
The tubular flowers of this plant attract long-tongued bees, including honeybees, bumblebees, Miner bees, Mason bees, and hummingbirds. Penstemons are called “Beard Tongues” because the sterile stamen has a tuft of small hairs. You may choose to pair Penstemon with some of these other native plants: Golden Alexanders (Zizia aurea), Spiderworts (Tradescantia ohiensis), and Prairie Blue-Eyed Grass (Sisyrinchium campestre). Other common names include Mississippi Penstemon, Smooth White Beardtongue, Talus Slope Penstemon, and simply, Beardtongue.
