A rare corpse flower is expected to bloom (and stink up) CSU this weekend

Get ready to meet Cosmo, the 8-year-old mostly dormant flower
Tammy Brenner, plant growth facility manager, measures “Cosmo,” an 8-year-old corpse flower (Amorphophallus Titanum) on May 16. The flower is about to bloom in the Plant Growth Facility Conservatory. (Courtesy of John Eisele/Colorado State University, via CPR)

A rare flower native to Indonesia is set to fully bloom in Fort Collins for the first time.

Since 2016, CSU’s College of Agricultural Sciences’ Conservatory has been caring for a “corpse flower,” the largest inflorescence – or collection of flowers acting as one – in the plant kingdom.

The International Union for Conservation of Nature estimates fewer than 1,000 corpse flowers remain in the wild.

The plant, which CSU calls “Cosmo,” remains dormant for most of the year. It only partially blooms once a year, creating a large, stemlike structure before returning to dormancy.

This year, however, Cosmo is expected to put on a show.

“Cosmo came out of dormancy around three weeks ago, and we didn’t expect anything exciting,” CSU plant growth facilities manager Tammy Brenner said in a statement. “But then two weeks ago, it started looking a little bit more full, a little bit more plump. It started growing and shooting out stalks, and we realized something really big was about to happen.”

What will it look and smell like?

Corpse flowers fully bloom only once every several years. When they do, they produce giant red flower buds with a pale stem protruding from the center.

The entire bloom lasts only a day or two.

Visitors crowd around a Titan arum, also known as the “corpse flower” in expectation of getting a whiff of its characteristic blooming smell of rotting flesh July 22, 2013, at the U.S. Botanic Garden in Washington. (Jacquelyn Martin/Associated Press file)

While the sight is pretty, the smell is what gave the species its name.

Corpse flowers emit a putrid odor while blooming that has been compared to the smell of decaying flesh. The smell helps the flower attract pollinators like carrion beetles and flies.

How to see Cosmo bloom

There’s no precise way to measure when Cosmo’s full bloom will happen, Brenner said, but CSU has set a tentative date of Saturday, May 25.

The Plant Growth Facility Conservatory will be open to the public from 9 a.m. to 3 p.m. each day the flower is in bloom.

To read more stories from Colorado Public Radio, visit www.cpr.org.

Tammy Brenner, CSU’s plant growth facility manager, measures Cosmo. (Courtesy of John Eisele/Colorado State University, via CPR)
Tammy Brenner, plant growth facility manager, measures “Cosmo,” an 8-year old Corpse Flower (Amorphophallus Titanum) that is about to bloom. (Courtesy of John Eisele/Colorado State University, via CPR)