A rare corpse flower is expected to bloom (and stink up) Colorado State University this weekend

Colorado State University
John Eisele/Colorado State University
Tammy Brenner, Plant Growth Facility Manager, measures “Cosmo,” an 8-year-old corpse flower (Amorphophallus Titanum) that is about to bloom in the Plant Growth Facility Conservatory,May 16, 2024

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, stem-like 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 the fully bloomed corpse flower look and smell like?

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

The entire bloom only lasts for a day or two.

Giant Stinky Flower
AP Photo
Here's what a corpse flower looks like. This one was in Washington D.C.

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 (and how long you'll have to wait if you miss it)

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. 

Colorado State University
John Eisele/Colorado State University
Tammy Brenner, CSU's plant growth facility manager, measures Cosmo.
Colorado State University
John Eisele/Colorado State University
Tammy Brenner, Plant Growth Facility Manager, measures "Cosmo," an 8-year old Corpse Flower (Amorphophallus Titanum) that is about to bloom in the Plant Growth Facility Conservatory. May 16, 2024

Those who miss Cosmo’s bloom will have to wait years for the next one.

The Denver Botanic Gardens cares for two corpse flowers — lovingly named “Lil’ Stinker” and “Stinky” — that last bloomed fully in 2022.