Wild Things

Big, Bad Botany: Oleander (Thevetia Peruviana), the Beautiful “Exit Plan”


Illustration by Carol Ann Lane

All week on Wild Things, we’ll be presenting our favorite dangerous, horrifying, and monstrous plants, excerpted from The Big, Bad Book of Botany: The World’s Most Fascinating Flora by Michael Largo. Out now from William Morrow.

Oleanders are beautiful bushes with lance-shaped, dark green leaves with a waxy finish that bloom large whorled pink, white, red, and yellow flowers that smell similar to apricots. The plant originated in the Mediterranean region and, because it grows quickly in a burst of color, early settlers transported it around the world to beautify and give “hostile” lands what they considered a civilized look. Oleanders thrive primarily in warmer climates; often found growing in the vacant lots of warmer California and Florida, some varieties of oleander can survive the summers of slightly cooler regions, and are used frequently by gardeners and landscapers to add a quick-growing burst of color.

“Be-still tree” and “lucky nut” are common names of a few oleander species, but each is extremely deadly. Just a nibble of a few of its leaves, or just a sampling of its black nuts, can cause vomiting and quite often a rapid death. Oleanders contain a chemical classified as a cardiac glycoside. These deadly chemicals affect the heart, causing wildly erratic beats and irregular constrictions and contractions; the human nervous system begins freaking out, as it were, which proves speedily fatal if induced vomiting or a stomach pump is not employed within minutes. Oleander ranks in the top five ornamental plants that cause fatalities. Ancient societies were well aware of its fast-acting poison and, because even a small amount proves deadly, it was often the food additive of choice for would-be assassins.

Though it’s important to be aware of plants and their more dangerous qualities, sometimes informing the public can bring unintended consequences. In Sri Lanka, for example, a television program designed to raise awareness of the oleander’s poisonous nature led to a string of suicides among young women, causing the statistic to jump from just two to nearly 200 in only three years. Among the elderly, the more botanically savvy have been known to select the oleander as their exit plan, as the lovely plant adorns the grounds of many nursing homes. Hence the nickname “be still” for this swift killer.

Oleanders’ toxins are in all parts of the plants, such that a few leaves that might fall into a dog’s water bowl are enough to kill it. Even campfires mistakenly built from the wood can cause deadly fumes, and urban legends tell of a whole troop of scouts who died, or fell seriously ill, after using the sticks of oleander to roast hot dogs. Oleander nectar gathered by bees and transformed into honey also contains toxins. Just 100 grams of the plant could cause a horse to keel over within minutes.

Excerpted from The Big, Bad Book of Botany: The World’s Most Fascinating Flora by Michael Largo. Out now from William Morrow, an imprint of HarperCollins Publishers. Reprinted by permission.