Yellow Oleander (Thevetia)

Yellow Oleander, botanically classified as Cascabela thevetia (formerly Thevetia peruviana) and famously celebrated in Indian culture as Pila Kaner, Lucky Nut, or the Be-still Tree, is a highly ornamental, heat-loving evergreen large shrub or small tree. Belonging to the dogbane family Apocynaceae (tribe Plumerieae), this striking tropical species is native to Central and South America and Mexico, but has naturalized extensively across tropical and subtropical regions worldwide, especially in India, Southeast Asia, Australia, and the Caribbean.

The plant typically grows 8 to 20 feet (2.5 to 6 meters) tall with an open, gracefully vase-shaped or rounded crown spreading 8 to 15 feet wide. It is densely cloaked in long, slender, glossy dark-green linear leaves measuring 3 to 6 inches long and just 0.25 to 0.5 inches wide, featuring rolled (revolute) edges and a prominent raised pale green midrib. The foliage is arranged spirally or in tight clusters along smooth, greyish-green woody branches that exude a copious, milky white latex sap when cut or bruised.

From late spring through autumn (and year-round in frost-free tropical climates), Yellow Oleander produces profuse clusters of showy, bell-shaped to funnelform flowers at branch tips. Individual blossoms measure 2 to 3 inches long and 1.5 to 2 inches wide, displaying a vivid bright golden-yellow or warm apricot-peach hue with a pleasant, delicate fragrance. The corolla features 5 overlapping, spirally contorted (twisted) petal lobes that flare widely from a narrow tubular throat equipped with five small hairy protective scales.

The actinomorphic reproductive morphology of Cascabela thevetia is represented by the family-specific floral formula ⊕ ⚥ K(5) [C(5) A5] G(2). This formula describes a radially symmetrical (actinomorphic), bisexual flower with a deeply 5-lobed calyx of acute green sepals. The corolla consists of 5 fused petals forming a funnelform tube with a contorted aesthetic in bud. Five stamens with short filaments are inserted (epipetalous) directly into the corolla throat, alternating with internal throat scales. The superior ovary is bicarpellary with a single style terminating in a large, disc-like stigma.

Following flowering, the plant produces distinctive, hard, angular drupaceous fruits that measure 1 to 1.5 inches in diameter with a unique rhomboid-triangular shape. The fruit begins bright green and fleshy, ripening to dull reddish-brown and ultimately a wrinkled blackish-purple. Inside lies a hard, woody, smooth triangular endocarp containing two to four seeds, historically known as 'lucky nuts' in traditional folklore.

For pet owners, veterinarians, and parents, Yellow Oleander demands the utmost caution: ALL PARTS OF THIS PLANT ARE EXTREMELY TOXIC AND POTENTIALLY LETHAL. Every tissue—especially the seeds and milky sap—contains dangerously potent cardiac glycosides, primarily thevetin A, thevetin B, thevetoxin, neriifolin, and peruvoside. Ingestion causes violent gastrointestinal irritation, profound bradycardia, cardiac arrhythmias, seizures, and fatal heart failure in cats, dogs, livestock, and humans. To study comprehensive clinical symptoms, decontamination protocols, and emergency guidance, see our specialized Pet Guard Profile for Oleander.

Yellow Oleander is easily distinguished from Common Oleander (Nerium oleander) by its radiant canary-yellow to peach funnel-shaped blooms and ultra-slender, willow-like linear leaves, whereas Common Oleander features broad lanceolate leaves and predominantly pink, red, or white flat-petaled blossoms. In frost-free ornamental landscapes, it is planted alongside tropical heat lovers like Oleander, Desert Rose, Plumeria, Allamanda, and Vinca. Explore our Flower Identifier to identify more tropical shrubs.

For more detailed botanical identification guides and toxicity audits, explore our companion profiles on Oleander (Rosebay), Desert Rose, and Plumeria.