Bloomipedia
Alpine sunflower (Hymenoxys grandiflora)
Photo: Bob Walker via iNaturalist · CC BY 4.0 · resized

Flower profile

Alpine sunflower

Hymenoxys grandiflora

Alpine sunflower (Hymenoxys grandiflora) is a flowering plant in the Asteraceae family, native in the lower 48 states, blooming mostly June–August across the U.S.

Native to Colorado

Alpine sunflower is a wildflower that USDA PLANTS lists as native in the lower 48 states. In Colorado it's most often seen in bloom in June–August.

5states where USDA records it
2,366CO sightings*
2,714U.S. sightings*

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

On our lists for: Colorado

Quick look

Hymenoxys grandiflora is a North American species of flowering plant in the daisy family known by the common names graylocks four-nerve daisy, graylocks rubberweed, or old man of the mountain. It is native to high elevations in the Rocky Mountains of the western United States.

  • It belongs to the Asteraceae family. iNaturalist
  • USDA PLANTS describes it as an herb (forb) with a perennial life cycle. USDA PLANTS
  • USDA PLANTS lists it as native in the lower 48 states and records it in 5 states. USDA PLANTS
  • NatureServe lists it as native to Colorado. NatureServe
  • In Colorado, most iNaturalist sightings of it in flower come in June–August. iNaturalist
  • iNaturalist has 2,366 research-grade sightings of it in Colorado, ranking #65 among the 160 flowers on our Colorado list. iNaturalist

When does it bloom?

In Colorado, most flowering sightings come in June–August.

Flowering records by month in Colorado (iNaturalist research-grade observations marked “Flowering”) (270 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
G4 Apparently secure worldwide. NatureServe
Colorado
No list Colorado has no state law listing endangered or threatened plants, so we show NatureServe's Colorado ranks instead. NatureServe: S4, apparently secure in Colorado.
Rare elsewhere
No other U.S. state ranks it S1, S2, SH or SX.

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 alpine sunflower in 5 states.

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Colorado, Idaho, Montana, Utah, Wyoming.

Colorado counties with USDA records: Archuleta, Boulder, Chaffee, Clear Creek, Dolores, El Paso, Garfield, Gilpin, Gunnison, Hinsdale, Jackson, La Plata, Lake, Larimer, Mineral, Park, Pitkin, Routt, Saguache, San Juan, Summit.

Names, range and relatives

Other scientific names (synonyms in USDA PLANTS): Actinea grandiflora, Rydbergia grandiflora.

County records: USDA PLANTS lists it in 44 counties across 5 states; the most are in Colorado (21), Wyoming (8), Montana (6).

Other Hymenoxys on Bloomipedia (1): Owlsclaws.

More from the Asteraceae family (212 on Bloomipedia; most observed first): Common yarrow, Goldenrods, White snakeroot, Sunflowers, Chicory, Black-eyed Susan, Bull thistle, Common dandelion.

More Colorado flowers

Rubber rabbitbrush (Ericameria nauseosa)

Rubber rabbitbrush

Ericameria nauseosa

Native

🌼 Blooms in CO: August–October
Common yarrow (Achillea millefolium)

Common yarrow

Achillea millefolium

Native

🌼 Blooms in CO: June–September
Dotted gayfeather (Liatris punctata)

Dotted gayfeather

Liatris punctata

Native

🌼 Blooms in CO: July–September

Sources