May's Flower of the Month

Oleander

(Nerium oleander)

Oleander is an easy-care, evergreen shrub or small tree with long, dark green leaves. During the summer, an abundance of single or double flowers in yellow, white, pink, or red bloom in terminal clusters. It grows well at the seashore, in highway medians with no irrigation, and in other difficult situations.  

Culture Oleander grows and flowers best in full sun. Although it is very drought tolerant, growth is faster and more vigorous when moisture is plentiful. Hardiness varies with variety. Standard types are hardy to the low teens while the dwarf varieties are tenderer. 

Prune if necessary to control size or shape. Remove suckers from base of plant as they will siphon off energy and inhibit flowering. Although oleander grows naturally into a rounded shrub, it can be pruned into a standard, or tree-like form.

Comments The oleander caterpillar is a serious pest which can defoliate a plant. The adult stage of the caterpillar is sometimes called the polka-dot wasp moth. This moth is easy to recognize. Look for a wasplike moth with body and wings that are a beautiful, iridescent blue-green. The body, wings, legs and antennae are covered with small white dots, and the tip of the abdomen is bright orange. To control, clip off and destroy infested shoots or spray with a product containing Bt (Bacillus thuringiensis).

All parts of oleander are poisonous. Chewing one leaf or twig can send a person to the hospital. Even the smoke resulting from burning the branches can be fatal. Many people suffer dermatitis after handling oleander stems or branches.

At a Glance

Say: NER-ee-um oh-lee-AN-der

 Hardiness: USDA Zones 8-10 

Salt tolerance: High

Family: Apocynaceae (Dogbane)

Size: 4-18 ft. tall/4-18 ft. wide

Other common names: None

Origin: Northern Africa, the eastern Mediterranean basin and southeast Asia

Relatives: Allamanda cathartica (allamanda); Catharanthus roseus, (Madagascar periwinkle)

Propagation: Cuttings

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