In late July we told you about the super-rare, foul-smelling corpse flower in bloom at the New York Botanical Garden. But that's far from the only one emitting its magnificent stench in America right now. Maybe you've heard about the one in Florida. Or Chicago. Or Washington D.C. Or maybe that one in Denver last summer? Amorphophallus titanum has been in bloom all across the country during the past year, which is pretty uncharacteristic for a flower that can take up to 15 years to show its flower. Stranger still, botanists don't understand why.

As Atlas Obscura reports, the University of Wisconsin tracked 157 corpse flower blooms between 1889 and 2008, which makes this sudden burst particularly notable. While it might seem logical for the same species of plant to be in sync, the corpse flower is a bit of a different beast. It’s rare in the wild, and doesn’t operate on a set timeline the way other perennials might.

Biology professor Daniel Janzen told The Wall Street Journal that the simultaneous blooms might have something to do with the flowers being from the same seed distribution, making the flora “cousins,” but that theory is impossible to prove.

Another hypothesis is that we’re seeing more blooms simply because there are more high-profile corpse flowers. Their popularity is good for botanical gardens, so many have given residence to the putrid plant in recent years and more overall logically leads to more blooms. But again, that doesn’t necessarily explain why all these corpse flowers are opening up at this particular moment.

The mystery continues—and the evidence is fading fast. Once in bloom, corpse flowers only last for about 36 hours.

[h/t Atlas Obscura]

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