CHAMPAIGN, Ill. - A rare tropical plant indigenous to the rainforests of Sumatra, Indonesia, is about to blossom in Central Illinois. An exotic titan arum, also called the "corpse flower" (Bunga Bankai) for the rotting-meat odor that the plant emits, is displaying characteristic signs that it is about to bloom, according to Debbie Black, the manager of the Plant Biology greenhouse on the University of Illinois campus where the plant was grown.
Graphic courtesy Mo Fayyaz, University of Wisconsin - Madison
Botanical elements of the titan arum
A member of the Araceae family and cousin of Calla lilies, peace lilies, dieffenbachia and philodendrons, the titan arum, latin name amorphophallus titanum, is notoriously difficult to cultivate and blooms unpredictably. Fewer than 100 corpse flowers have bloomed in cultivation in the U.S. since the first titan arum unfurled at the New York Botanical Gardens in 1937.
The U. of I.'s titan arum was grown from seed that was given to the university by Mo Fayyaz, a botanist at the University of Wisconsin at Madison who cultivated "Big Bucky," the first titan arum to bloom in Wisconsin. After the Wisconsin plant flowered in 2001, the seed was harvested and shared with Illinois and several other institutions.
"We've coddled it for 10 years," Black said about the U. of I.'s titan, which was named Titania following a poll of greenhouse visitors in 2010. "For about the first five years, I wouldn't let anybody touch it but me. That way, if it died, I could only get mad at myself and not at the students."
As Titania has neared maturity, it has been growing at an astonishing rate, shooting up 7 inches in three days, from 29 inches on Sunday (July 3) to 36 inches on Wednesday (July 6). Titania likely will grow another 1 to 2 feet before blooming about July 14-15, Black said.
Titan arums grow from an underground corm that can weigh 200 pounds or more. Titania's corm, which has outgrown and broken a succession of pots, weighed in at a petite 38 pounds on June 20.
If exposed to too much moisture in cultivation, the corms can rot easily. To prevent that, Titania is planted in a high porosity potting soil that conserves moisture while allowing quick drainage, Black said.
Like other tropical plants, titans require temperatures of 75 degrees or more and high humidity.
For most of its life, a titan arum cycles through periods of dormancy and activity, producing a single, umbrella-like leaf each year that can tower up to 20 feet tall and span 15 feet.
Last year, Titania's leaf began growing in March and towered at more than 9 feet tall before it began to die in December.
The plants typically bloom seven to 10 years after germination, producing a flower structure called an inflorescence, which comprises thousands of tiny flowers arranged around the base of a fleshy central column known as the spadix that is enclosed in a frilly-edged bud called the spathe.
When the plant blooms, the spathe unfurls suddenly, usually within a few hours, beginning in mid-afternoon. When fully open, the spathe reveals a maroon interior similar in appearance to raw meat and emits its signature corpselike smell to attract carrion beetles, flesh flies and other pollinators. To increase its chances of pollination, the plant burns stored carbohydrates to heat itself up, reaching near human body temperature at the tip of the spadix to disperse the fragrance as widely as possible.
The enormous amount of energy required to generate the bloom and diffuse the fragrance only allows the plants to bloom for 24-36 hours and prevents them from blooming annually. After the initial flowering, a titan may bloom every two to three years.
A titan arum has both female and male flowers, and to encourage cross-pollination with other plants the female flowers mature first, followed by the male flowers the next day. If pollinated, the plant produces a ball of bright red fruits the size of cherries, which birds consume, scattering the seeds in the environment.
Whether Titania will be pollinated after blooming remains to be seen. Rarely, a plant may self-pollinate.
"I have a tiny bit of pollen from Eastern Illinois University from when their titan bloomed a couple of years ago," Black said. "But that's 2-year-old pollen that's been in the freezer."
Other staff members with offices in the same building as the conservatory have been forewarned that Titania is about to flower - and unleash a foul odor.
Noxious odor or not, Black is excited that the plant the department has nurtured for a decade is about to flower.
"It's like giving birth to my firstborn child," Black said
A staff member from the company that produces the History Channel's "Modern Marvels" program contacted Black about filming the corpse flower's opening.
The greenhouses and plant collections, 1201 S. Dorner Drive, Urbana, are open to the public 8:30 a.m. to 4:30 p.m. Monday through Friday; hours may be extended and may include 9 a.m. to 3 p.m. Saturday, depending on when Titania blooms and on the number of visitors, Black said.
Photos and updates on Titania are on the Friends of the U. of I. Conservatory Facebook page, and on the greenhouses' Web page.