How-to Guide
How to Grow Penstemon
The short answer
Grow penstemon (beardtongue) in full sun and lean, well-drained soil; it tolerates drought and even brief flooding once established but rots in overly wet, poorly drained ground, so sharp drainage is the make-or-break factor. The tubular flowers attract hummingbirds, butterflies, and bees.
Match the species to your region: penstemon is a large, mostly North American genus centered in the arid West, where many species demand fast-draining, gritty soil, while easygoing eastern natives like Penstemon digitalis (hardy about zones 3–8) tolerate ordinary garden conditions and even clay. Pick a species adapted to your climate rather than fighting your soil.
Drainage is everything
The single most important thing about penstemon is drainage. Grow it in average, dry to medium-moisture, well-drained soil in full sun; it is tolerant of occasional drought and even brief inundation once established, but it will not survive overly wet, poorly drained conditions.
Heavy, soggy soil — especially in winter — is the usual way gardeners kill penstemon. If your ground is dense clay, plant on a slope or raised bed, or work in grit to open it up. Full sun and lean soil produce the stiff, upright habit and best flowering.
Skip heavy feeding and frequent irrigation of established plants; rich, wet conditions push floppy growth and shorten the plant's life.
Choose a species for your region
Penstemon is a big genus, almost entirely native to North America, with its center of diversity in the arid West — Utah, Colorado, and the Southwest hold the greatest number of species. Many of those western species are true drainage obsessives, at home in gritty, sunbaked, rock-garden conditions and quick to rot in a moist eastern border.
Eastern and prairie species are more forgiving. Penstemon digitalis (foxglove beardtongue), for instance, is a clump-forming native that grows three to five feet, tolerates clay, and is hardy zones 3–8 — a reliable choice for ordinary garden soil where a western alpine species would sulk.
So before buying, check whether the species you like is adapted to your rainfall and soil. Matching plant to place is more effective than trying to re-engineer your whole bed.
A pollinator plant that draws hummingbirds
The tubular, two-lipped flowers are made for pollinators. Penstemon digitalis blooms from mid-spring into early summer and is attractive to hummingbirds, butterflies, and other pollinators, filling an early-season nectar niche in a pollinator garden.
Plants tend to be deer-resistant and make good cut flowers. Leave the seed stalks standing if you want self-sown seedlings or winter structure; otherwise cut back after bloom for a tidy clump.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- Missouri Botanical Garden Plant Finder — Penstemon digitalis — 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; clump-forming Missouri native growing 3–5 feet; white tubular flowers bloom mid-spring to early summer and attract hummingbirds and butterflies; hardy zones 3–8; tolerates deer, drought, clay, and dry soil.