Oleander Species

Physical Description

• Oleander’s thick, fibrous leaves are shaped like spears growing in opposition to each other. If the plants are grown outdoors, the leaves reach lengths between 8 and 10 inches. Leaves on houseplants are considerably shorter. The flowers range from white to cream, yellow, pink, red and purple, have five 1 to 3 inch wide lobes and grow in big clusters at the ends of branches. Some oleander flowers have barely discernible scents.

Cultivation

• Oleander is a hardy plant that grows in most type soil. It tolerates light frost, although the flowers and leaves may show slight damage from the cold. It thrives in partial shade to full sun and survives periods of drought. Since oleander is unaffected by salty air, it is often planted in regions near seas, oceans and bays.

Toxicity

• Every part of the oleander plant is highly toxic to humans and animals, as it contains cardiac glycosides including oleandrin and nerioside. Oleander sap is used as rat poison. Pets, livestock and birds that consume its fresh, wilted or dried leaves or flowers are likely to die. Although its taste is not appealing, bored or extremely hungry animals will eat it. Thirty or 40 leaves will kill a full-grown horse. Oleander should not be grown where animals are present or in areas where the fallen leaves or flowers may be blown into neighboring pastures or yards.

Symptoms and Treatment

• Oleander poisoning happens so quickly that animals often die before developing common symptoms including vomiting, diarrhea, irregular heartbeat, listlessness and abdominal distress. As the poisoning progresses, the animal’s limbs become cold and its mucous membranes fade from pink or red, to white. If you witness an animal eating oleander, immediately contact a veterinarian, who may give the animal drugs promoting vomiting or regulating the animal’s heart rate. Even with swift and professional medical attention, most animals do not survive oleander poisoning.