"Environmental Guardian" Is oleander poisonous? Can it be kept indoors? When does it bloom?

Oleander, also known as Bitao, Baiyangtao, Jiujiezhong, Liuyetao and so on, is often cultivated in parks, scenic areas, along roadsides, riversides or lakesides. So is oleander poisonous? Can it be kept indoors? When does it bloom?

Oleander originated in India and has strong adaptability, so it was widely introduced around the world very early on. Oleander, of the tribe Nerieae and genus Nerium, is an evergreen upright large shrub that can reach 5 m in height, with grayish-green branches; young branches are angular and slightly hairy, losing their hairs when old. Leaves are in whorls of 3-4, dark green on the upper surface and light green on the underside, with the midrib sunken on the upper surface; the petiole is flat, the cyme is terminal, the corolla is deep red or pink; when the corolla is single-layered and 5-lobed, it is funnel-shaped; the seeds are oblong.

Is oleander poisonous?

Oleander was first introduced and cultivated as an ornamental garden plant during the Tang and Song dynasties, but what made it most famous worldwide was not its delicate and beautiful flowers, but its toxicity.

The entire oleander plant contains extremely strong toxins that can cause death in humans and animals, and there have been reports of death from small amounts. The whole plant contains multiple toxins, of which the most abundant are cardiac glycosides. The leaves, bark, roots and pollen of oleander are all toxic, with the highest concentration of toxins in the sap. The milky white sap it secretes is rich in oleandrin, and poisoning is very likely after accidental ingestion. Even more astonishing is that the toxicity of oleander persists even after it dries out, and the smoke produced when it is burned is also highly toxic.

Symptoms of oleander poisoning

Oleander poisoning mainly presents as digitalis poisoning symptoms, and may include nausea, vomiting, abdominal pain, diarrhea, slow heartbeat or tachycardia, arrhythmia, and may be accompanied by fever, difficulty breathing, cyanosis, blurred vision, red rash around the mouth, and finally syncope, convulsions, coma, and ectopic rhythms; electrocardiography may show bradycardia, conduction block and various other types of arrhythmia, with death often resulting from ventricular fibrillation and circulatory failure.

Therefore, although oleander is beautiful, it is still not suitable for widespread use as an ornamental flower, especially for home flower growing, so it is not recommended to keep it indoors. When viewing this flower, do not touch the white sap secreted from the flowers, stems and leaves. Children should also be informed and educated not to pick or chew the flowers and leaves casually.

So then, this poisonous oleander, why is oleander still planted despite being poisonous?

Because oleander is one of the plants with the strongest dust-absorbing ability in the world, and is known as a natural “green vacuum cleaner.” Its ability to absorb and resist harmful gases such as sulfur dioxide, chlorine gas and hydrogen fluoride is very strong, and it can also retain smoke and dust; even if its whole body is covered with dust, it can still grow vigorously. According to measurements, potted oleander at 40 m from a pollution source suffers only mild damage, and at 170 m it is basically unharmed and can still bloom normally, and the sulfur content in its leaves is more than 7 times higher than that of unpolluted plants. Even if its whole body is covered with dust, oleander can still grow vigorously, and people call it the "Environmental Guardian."

When does oleander bloom?

Oleander has a long flowering period, almost year-round, with summer and autumn being the peak season; the flowers are delicate and beautiful. Whenever the flowering season comes, it produces dense clusters of white or peach-red flowers, adorning our cities. Whenever it blooms, it always attracts crowds to take group photos, and some even pick the flowering branches for young children to play with. In fact, this kind of “close contact” with oleander is very dangerous.

Reminder: in the presence of this beautiful “Environmental Guardian,” please keep your distance and never play with it up close.