Botanic Superlatives: The Largest Flower

Botanic Superlatives: The Largest Flower

February 18, 2011
Photo by: Troy Davis

Despite its efforts to keep a low profile—lurking, as it tends to do, deep in Southeast Asia's undisturbed rainforests—the Rafflesia arnoldii has international notoriety. Its detractors might call it a hulking, smelly parasite, and they would not be wrong. Also known as the "stinking corpse lily," the infamous plant blooms with the world's largest individual flowers that give off a noxious odor that happens to attract carrion beetles and flies (the plant's preferred jungle-dwelling pollinators). The five-lobed fleshy blossom is unmistakably red, and unmatchably large: at 3' in diameter and 25 pounds in weight, it's a spectacle and a fantastic oddity.

The curious plant has evolved with a dilemma: it lacks leaves, stems, or even roots. But that's not a problem in the rainforest, since the Rafflesia arnoldii grows endo-parasitically within a certain vine (Tetrastigma). Embedding itself in these stems, the plant gleans all necessary nutrients from its host, and remains hidden and wrapped in the woody growth for most of its life cycle. And so it grows, nurturing nascent blossoms, and it waits.

The bud is first to emerge: resembling an apricot-colored head of lettuce, it surges through the vine's bark and explodes into the aforementioned spectacle of a blossom. An aroma of rotting meat saturates the jungle miasma, and insects gather to ferry pollen from male to female flowers. The pollinated ovaries can yield up to four million seeds, which are dispersed by a fleet of rainforest animals, including Asian elephants, wild pigs, tree shrews, and ants. Indiscriminately scattered under the canopy, most of the seeds will disappear. Out of the millions of seeds, only a couple will find themselves lodged on the host vine. Then, if sufficiently damp and shielded, the seed will germinate and proliferate a network of tissue inside the vine's rich stem. And the Rafflesia arnoldii is once again undercover, under bark, nurturing its superlative crimson progeny.  

Anna Laurent is a writer and producer of educational botanical media. Photographs from her forthcoming field guide to Los Angeles are available for exhibition and purchase at the author's shop