Penstemon strictus

Common Names

Rocky Mountain Penstemon, Rocky Mountain Beardtongue, Beardtongue, Strict Beardtongue

Summary

Rocky Mountain penstemon is a perennial native to the western United States that forms large clumps from a thick crown, with basal and cauline opposite leaves and erect spikes of blue to deep violet-blue tubular flowers arranged on one side of the stem; the flowers have a two-lobed upper lip, a three-lobed lower lip, and a white throat often with violet markings, and the plant is drought-tolerant in well-drained soils found in rocky, sandy meadows and woodlands at elevations around 6,000–10,500 ft.

It prefers full sun to partial shade and well-drained soils, tolerating sandy, loamy, or gravelly substrates; supplemental water in the first year aids establishment, then drought tolerance persists. Hardiness zones 4–9; propagation by seed or root division, with seeds requiring cold stratification for about 2–3 months and germination around 16°C. Commonly used in rock gardens, native plantings, xeriscapes, and roadside plantings, and it attracts bees and hummingbirds.

Lifecycle

Perennial

Height

1-3 feet

Spread

2-3 feet

Hardiness Zones

Zones 3-8

Sunlight Requirements

Full Sun to Partial Shade.

Soil Type

Well-drained soil, sandy or loamy.

Soil Drainage

Well-drained soil

Soil pH

Tolerates all pH levels

Bloom Color

Blue to purple

Bloom Time

Summer

Foliage Color

Blue-green, Dark green, Emerald green, Green

Fall Foliage Color

Green

Leaf Lifecycle

Evergreen broadleaf

Growth Rate

Moderate

Seasons of Interest

Spring and Summer

Propagation Methods

Seeds, Division, Cuttings

Attracts Wildlife

Attracts bees, hummingbirds, butterflies, other pollinators, and birds