Bloomipedia
Be-still tree (Cascabela thevetia)
Photo: stinger via iNaturalist · CC BY 4.0 · resized

Flower profile

Be-still tree

Cascabela thevetia

Introduced in the lower 48

Be-still tree is a flowering plant that USDA PLANTS lists as introduced in the lower 48 states.

3states
500HI sightings*
621U.S. sightings*

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

On our lists for: Hawaii

Quick look

Cascabela thevetia is a species of poisonous plant in the dogbane family Apocynaceae, native throughout Mexico and Central America and cultivated widely as an ornamental. It is a relative of Nerium oleander and thus is known by the common name yellow oleander.

  • It belongs to the Apocynaceae family. iNaturalist
  • USDA PLANTS describes it as a shrub / a tree with a perennial life cycle. USDA PLANTS
  • USDA PLANTS lists it as introduced in the lower 48 states and records it in 3 states. USDA PLANTS
  • iNaturalist has 500 research-grade sightings of it in Hawaii, ranking #98 among the 105 flowers on our Hawaii list. iNaturalist

Be-still tree gift ideas

Handmade be-still tree gifts from independent makers.

🌱 Sample spot. Handmade gift picks from independent shops will appear here once our shop partnership is approved. These cards are placeholders, not real products.

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    Be-still tree art print

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    Be-still tree greeting card

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    Be-still tree mug

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    Be-still tree earrings

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    Be-still tree embroidery pattern

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    Be-still tree sticker

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When does it bloom?

Flowering records by month across the U.S. (iNaturalist research-grade observations marked “Flowering”) (43 records)

There are only a handful of Hawaii flowering records, so this chart uses records from across the U.S.

Conservation status

Federal (U.S. ESA)
Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. USFWS ECOS
NatureServe
Unknown We couldn't find this name in NatureServe Explorer. 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. HAR 13-107

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

Can you eat it?

For peopleCaution: partly edible, partly poisonous

NC State Extension lists it as poisonous to humans (severity: high). Poisonous parts: sap/juice. Symptoms they list: “All parts of the plant are poisonous if ingested and the sap can cause allergic skin reactions in some people. Smoke from burning plant material can be toxic.” They also note: “All parts of the plant are toxic.” NC State Extension

For petsCan be a problem for cats, dogs and horses

NC State Extension flags it as a problem for cats, dogs and horses. It isn't on the ASPCA plant list. NC State Extension

🌿 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 be-still tree in 3 states.

recorded by USDA PLANTS on our state lists not recorded

See the full list of states

Florida, Hawaii, Texas.

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

More Hawaii flowers

Madagascar periwinkle (Catharanthus roseus)

Madagascar periwinkle

Catharanthus roseus

Introduced

🌼 Blooms in HI: January–December
Zulu giant (Stapelia gigantea)

Zulu giant

Stapelia gigantea

Introduced

🌼 Blooms in HI: March–December
ʻōhiʻa lehua (Metrosideros polymorpha)

ʻōhiʻa lehua

Metrosideros polymorpha

Native

🌼 Blooms in HI: January–December

Sources