Bloomipedia
Hot rock penstemon (Penstemon deustus)
Photo: Daniel Kennedy via iNaturalist · CC BY 4.0 · resized

Flower profile

Hot rock penstemon

Penstemon deustus

Native to Idaho

Hot rock penstemon is a wildflower that USDA PLANTS lists as native in the lower 48 states. In Idaho it's most often seen in bloom in May–July.

8states
555ID sightings*
2,217U.S. sightings*

*iNaturalist research-grade observations, as of October 17, 2026.

On our lists for: Idaho

Quick look

Penstemon deustus is a species of penstemon known by the common names hotrock penstemon and scabland penstemon. It is native to much of the northwestern United States from the Pacific Northwest to Wyoming, where it grows in many types of forest and open plateau habitat, often on soils heavy in volcanic rock or on limestone outcrops.

  • It belongs to the Plantaginaceae family. iNaturalist
  • USDA PLANTS describes it as an herb (forb) / a subshrub with a perennial life cycle. USDA PLANTS
  • USDA PLANTS lists it as native in the lower 48 states and records it in 8 states. USDA PLANTS
  • NatureServe lists it as native to Idaho. NatureServe
  • In Idaho, most iNaturalist sightings of it in flower come in May–July. iNaturalist
  • USDA PLANTS lists its flower color as yellow. USDA PLANTS
  • USDA PLANTS gives its bloom period as late spring. USDA PLANTS
  • USDA PLANTS lists a mature height of about 2 ft. USDA PLANTS
  • iNaturalist has 555 research-grade sightings of it in Idaho, ranking #55 among the 109 flowers on our Idaho list. iNaturalist

Hot rock penstemon gift ideas

Handmade hot rock penstemon gifts from independent makers.

When does it bloom?

In Idaho, most flowering sightings come in May–July.

Flowering records by month in Idaho (iNaturalist research-grade observations marked “Flowering”) (30 records)

Conservation status

Federal (U.S. ESA)
Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. USFWS ECOS
NatureServe global
G5 Secure worldwide. NatureServe
Idaho
No list Idaho has no state law listing endangered or threatened plants, so we show NatureServe's Idaho ranks instead. NatureServe: SNR, not yet ranked in Idaho.
Rare elsewhere
Other states where NatureServe ranks it rare or missing: UT (S1). (S1 critically imperiled, S2 imperiled, SH possibly extirpated, SX presumed extirpated.)

Checked October 17, 2026. Rankings and lists can change, so follow the links for the latest.

Can you eat it?

For peopleNot well documented

None of the sources we checked (NC State Extension (no page for this plant), USDA PLANTS) say whether it's edible or poisonous for people.

For petsNot well documented

It isn't on the ASPCA plant list.

🌿 Never eat a wild plant unless you're certain of its ID; this isn't medical advice. Worried about a person? Call Poison Control at 1-800-222-1222. Worried about a pet? Call your vet.

Where does it grow?

USDA PLANTS records hot rock penstemon in 8 states.

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

California, Idaho, Montana, Nevada, Oregon, Utah, Washington, Wyoming.

Idaho counties with USDA records: Ada, Adams, Bannock, Bingham, Blaine, Boise, Bonner, Bonneville, Butte, Cassia, Clark, Custer, Elmore, Fremont, Gem, Idaho, Kootenai, Lemhi, Lincoln, Madison, Owyhee, Payette, Shoshone, Twin Falls, Valley, Washington.

More Idaho flowers

Sources