Fans of unusual flora who have been holding their breath can now hold their noses. Two rare corpse flowers are about to bloom — one at the United States Botanic Garden in Washington, D.C. and another at the New York Botanical Garden in the Bronx.

Officially called Amorphophallus titanium, the giant plant is native to Sumatra and hails from the same family as peace and calla lilies. The towering plant takes at least seven years to bloom and, when it does, everyone knows it.

The plant lets off an overpowering stench comparable to rotting flesh — although others say it smells more like a really stinky diaper, rotting fish or spoiled eggs. The bloom and the smell typically start to fade after a day but can last for up to 48 hours.

Why the nasty odor? It would be difficult for a smaller, sweeter-smelling plant to attract would-be pollinators in the dense jungles of Sumatra, so this plant reaches for the opposite end of the spectrum. By emitting a horrendous stink, the plant lures carrion flies and beetles, which normally feed on rotting flesh.

The corpse flower isn't really a single flower at all but a cluster of many flowers arranged on a stem (called an inflorescence). The flowers are hidden out of sight at the bottom of the central stalk structure, the spandix. That's surrounded by the spathe — a ruffled covering that's green on the outside and deep burgundy inside that's visible when it opens up to bloom.

The plant is also known as Titan arum, a name first used by famed British naturalist Sir David Attenborough in the BBC series "The Private Lives of Plants." He reportedly felt viewers might be offended by the plant's Latin name which translates to mean "giant misshapen penis."

Editor's note: This story has been updated since it was originally published in August 2015.

Mary Jo DiLonardo Mary Jo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.