Flower profile

Purple clematis

Clematis occidentalis

Purple clematis (Clematis occidentalis) is a vine in the Ranunculaceae family, native in the lower 48 states, blooming mostly May–June across the U.S.

Native in the lower 48

Purple clematis is a flowering plant that USDA PLANTS lists as native in the lower 48 states. It's on our flower lists for 2 states, and across the U.S. it's most often seen in bloom in May–June.

27states where USDA records it

2Bloomipedia state lists include it

2,926U.S. sightings*

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

On our lists for: Montana, Wyoming

Quick look

Clematis occidentalis is a species of flowering plant in the buttercup family known by the common names western blue virginsbower or purple clematis. It is native to much of southern Canada and the northern United States.
From Wikipedia's article Clematis occidentalis, CC BY-SA 4.0.

It belongs to the Ranunculaceae family. ^iNaturalist
USDA PLANTS describes it as a vine with a perennial life cycle. ^{USDA PLANTS}
USDA PLANTS lists it as native in the lower 48 states and records it in 27 states. ^{USDA PLANTS}
NatureServe lists it as native to Montana and Wyoming. ^NatureServe
iNaturalist has 811 research-grade sightings of it in Montana, ranking #49 among the 128 flowers on our Montana list. ^iNaturalist
iNaturalist has 368 research-grade sightings of it in Wyoming, ranking #76 among the 113 flowers on our Wyoming list. ^iNaturalist

When does it bloom?

Flowering records by month across the U.S. (iNaturalist research-grade observations marked “Flowering”) (302 records)

Bloom time in the 2 states whose Bloomipedia list includes it

State	Type	Peak bloom	Sightings*
Montana	Native	few records (45)	811
Wyoming	Native	few records (15)	368

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
Montana: No list Montana has no state law listing endangered or threatened plants, so we show NatureServe's Montana ranks instead. NatureServe: S4, apparently secure in Montana.
Wyoming: No list Wyoming has no state law listing endangered or threatened plants, so we show NatureServe's Wyoming ranks instead. NatureServe: S4, apparently secure in Wyoming.
Rare elsewhere: Other states where NatureServe ranks it rare or missing: DE (SX), IA (S2), IL (S1), MA (S2), MD (S1), NC (S1), OH (SX), PA (S2), RI (S1), VA (S2), WV (S2). (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 petsToxic to dogs, cats and horses

ASPCA's entry “Leatherflower” (Clematis sp), which covers the whole genus, lists it as toxic to dogs, cats and horses. Signs include: Salivation, vomiting… ^ASPCA

🌿 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 purple clematis in 27 states.

AKMEVTNHWAIDMTNDMNILWIMINYRIMAORNVWYSDIAINOHPANJCTCAUTCONEMOKYWVVAMDDEAZNMKSARTNNCSCDCOKLAMSALGAHITXFL

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Colorado, Connecticut, Delaware, Idaho, Illinois, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oregon, Pennsylvania, Rhode Island, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin, Wyoming.

Montana counties with USDA records: Phillips.

Wyoming counties with USDA records: Albany, Big Horn, Carbon, Converse, Fremont, Johnson, Laramie, Lincoln, Park, Teton.

Names, range and relatives

Native status by region (USDA PLANTS): Canada: Native; Lower 48 states: Native.

County records: USDA PLANTS lists it in 191 counties across 24 states; the most are in New York (27), Pennsylvania (26), Wisconsin (24).

Other Clematis on Bloomipedia (6): Virgin's bower, Autumn clematis, Old man's beard clematis, Hairy clematis, Western white clematis, Swamp leatherflower.

More from the Ranunculaceae family (48 on Bloomipedia; most observed first): Lesser celandine, Rue anemone, Red columbine, Wood anemone, Western columbine, Marsh marigold, White baneberry, Round-lobed hepatica.

More Montana flowers

Yellow columbine

Aquilegia flavescens

Native

🌼 Blooms in MT: June–August

Prairie pasqueflower

Pulsatilla nuttalliana

★ SD state floral emblemNative

🌼 Blooms in MT: April–June

Red baneberry

Actaea rubra

Native

🌼 Few flowering records in MT

Sources

USDA, NRCS. PLANTS Database, profile CLOC2.
iNaturalist, Clematis occidentalis: taxonomy, research-grade observation counts and “Flowering” annotations, retrieved October 17, 2026.
Wikipedia, Clematis occidentalis (lead quoted under CC BY-SA 4.0).
Montana: Montana noxious weed list (Admin. R. Mont. 4.5.206–4.5.210).
Wyoming: Wyoming state designated noxious weeds (W.S. 11-5-102(a)(xi)), as listed by the Wyoming Weed & Pest Council.
USFWS, ECOS species database (ESA listing check), October 17, 2026.
NatureServe Explorer, Clematis occidentalis (global and state ranks).
Edibility and toxicity: ASPCA.
Photo: Erik Schiff via iNaturalist · CC0 · resized.