Bloomipedia
Rattleweed (Crotalaria retusa)
Photo: David Anderson via iNaturalist · CC BY 4.0 · resized

Flower profile

Rattleweed

Crotalaria retusa

Not native to Hawaii

Rattleweed is a wildflower that USDA PLANTS lists as introduced in the lower 48 states. In Hawaii it's most often seen in bloom in January–October.

10states
572HI sightings*
790U.S. sightings*

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

On our lists for: Hawaii

Quick look

Crotalaria retusa is a species of flowering plant in the legume family known by various common names including devil-bean, rattleweed, shack shack, and wedge-leaf rattlepod. It is poisonous to livestock, and contaminates human food. Its original native range is unclear, probably including tropical Asia, Africa and Australia.

  • It belongs to the Fabaceae family. iNaturalist
  • USDA PLANTS describes it as an herb (forb) / a subshrub with a annual life cycle. USDA PLANTS
  • USDA PLANTS lists it as introduced in the lower 48 states and records it in 10 states. USDA PLANTS
  • NatureServe lists it as not native to Hawaii. NatureServe
  • In Hawaii, most iNaturalist sightings of it in flower come in January–October. iNaturalist
  • iNaturalist has 572 research-grade sightings of it in Hawaii, ranking #87 among the 105 flowers on our Hawaii list. iNaturalist

Rattleweed gift ideas

Handmade rattleweed gifts from independent makers.

When does it bloom?

In Hawaii, most flowering sightings come in January–October.

Flowering records by month in Hawaii (iNaturalist research-grade observations marked “Flowering”) (37 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
Hawaii
Not listed Not on Hawaii threatened and endangered plants (HAR 13-107; the state list follows the federal list), DLNR Division of Forestry and Wildlife. NatureServe: SNA, not applicable (usually because it isn't native there) in Hawaii. HAR 13-107
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. For context only: ASPCA lists a related species, Crotalaria albida (“Rattlebox”), as non-toxic to dogs and cats. That doesn't tell us about this species, so keep pets away to be safe. 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 rattleweed in 10 states.

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Florida, Georgia, Hawaii, Kentucky, Louisiana, Mississippi, New Jersey, North Carolina, South Carolina, Texas.

Hawaii counties with USDA records: Hawaii, Honolulu, Kauai, Maui.

More Hawaii flowers

Sources