The leaves appear opposite or in whorls of three. They art lance shaped, entire and somewhat leathery. The showy clusters of flowers are located at the ends of branches and vary in color from white to pink and red. Oleanders were introduced from the Mediterranean and Asiatic regions and are now very popular as potted ornamentals and roadside planting.
Oleander contains two major cardiac glycosides, oleandroside and nerioside.
All parts of the oleander, both green and dry, are extremely toxic. One leaf is considered sufficient to kill an adult. Numerous poisonings have resulted from using the branches to skewer frankfurters or other foods for roasting over open fires. Children have been poisoned by sucking nectar from the blossoms or by chewing the leaves. Honey made from oleander is poisonous.