Hot Rock Penstemon in the Landscape

Diane Jones, Draggin' Wing Farm, Water-thrifty Plants for Idaho

Scientfic Name:  Penstemon deustus
Common Name:  Hot Rock Penstemon, Scorched Penstemon, Scabland Penstemon

Description:  Small creamy white tubular flowers over a woody base with thick, leathery serrated leaves. Does well in dry, rocky conditions and likes gravel mulch.

Native Habitat:  Grows in exposed, rocky sites from Eastern Washington south to N. California and east to Western Montana and NW Utah at elevations ranging from 3,000 to 8,000 feet.

Cultural Requirement

Soil:  Well-drained, shallow, nutrient-poor or ordinary garden soil.

Moisture Tolerance:  Very xeric.

Sun/Shade/Preference:  Full sun.

Transplanting:  Easy.

Propagation:  Seed or cuttings.

Maintenance (pruning, fertilization, deadheading, division, irrigation, etc):  Remove spent flower heads for neater appearance.

Insect, disease, or other problems:  None of concern.

Landscape Value

Use in the Landscape:  Valuable for hot, dry rocky areas of the xeric garden.

Foliage:  Serrated dark green, leathery leaves.

Flower:  Small (1/2") cream or white tubular flowers with lavender stripes from mouth to throat that serve as nectar guides.

Timing:  May-June.

Color:  White-cream.

Form:  Open mound, somewhat woody, with flower stalks overhead.

Texture:  Leaves leathery, stalks woody and relatively stiff.

Ultimate Size:  12-18" tall x 12" wide.

Rate of Growth:  Slow to moderate growth.

Suggested Plant Partners:  Sagebrush, Rabbitbrush, Sulfur Buckwheat.

Availability:  Available at specialty nurseries.

Cultivars:  Four recognized subspecies.

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