Common Name: yellow oleander
Type: Broadleaf evergreen
Native Range: Tropical America
Zone: 8 to 10
Height: 4.00 to 8.00 feet
Spread: 4.00 to 5.00 feet
Bloom Time: Seasonal bloomer
Bloom Description: Yellow
Sun: Full sun to part shade
Flower: Showy, Fragrant
Winter hardy to USDA Zones 8-10. In St. Louis, grow in containers or tubs that are overwintered indoors or as year-round houseplants. Container plants may be grown as shrubs or trained as ornamental standards. Plants generally grow best when overwintering period is short. Overwinter in a cool location (40s F.), such as a basement or garage, with moderate light and very little water or as a houseplant in a bright sunny but cool room with reduced water. Grows well in average, medium moisture soils in full sun to part shade. Thrives in rich, sandy soils. Container plants do best in fertile soils with good drainage. Water regularly but let plant soils dry out between waterings. Promptly deadhead spent blooms to prevent formation of non-ornamental seed pods. Cuttings may be taken in late summer. Prune lightly as needed to shape after flowering (late summer to fall).
Cascabela thevetia, commonly called yellow oleander, is native to the West Indies, southern Mexico and Belize. It is a tropical evergreen shrub or small tree that is in the same family as and closely related to Nerium oleander, commonly known as oleander. Primary differences between the two oleanders are: yellow oleander has yellow flowers and alternate leaves and oleander has pink or white flowers with leaves in whorls of three. Yellow oleander will grow to 20-30’ tall in its native habitat, but much shorter in the St. Louis area. It is an upright shrub that features willow-like, linear-lanceolate, glossy green leaves (to 6-7” long) with distinctive midribs and large 3” long funnel-shaped sometimes-fragrant yellow (less commonly apricot) flowers in few-flowered terminal clusters (cymes). Flowers bloom from summer to fall. Flowers give way to black seed pods, each containing 1-2 nut-like seeds. As with many of the dogbane family members, plant stems exude a milky sap when cut and all parts of the plant are poisonous if ingested. Plant saps can cause allergic skin reactions in some people. Smoke from burning plant material can also be toxic. May be trained as a standard. Seeds (1” diameter) are sometimes carried as talismen in the West Indies, where the shrubs are also commonly called lucky nut.
Synonymous with Thevetia peruviana and Cascabela peruviana.
Genus name honors 16th century French Franciscan monk Andre Thevet who accompanied a French expedition to Brazil in the 1550s.
No serious insect or disease problems. Watch for mealybugs, aphids and scale. Caterpillars may chew on the foliage. Remove and destroy any leaves damaged by leaf spot.
Container plant for sunny decks, patios and other locations around the home. In Zones 8-10, these plants are used in a variety of landscape applications including hedges, screens, foundation plantings and borders.