Update: This flower is no longer blooming.
Amorphophallus titanum (Araceae)
Titan arum (Aroid Family)
This week’s featured plant is a real treat. Often called one of the largest flowers in the world, the “bloom” is actually the largest unbranched inflorescence (flower cluster) in the plant kingdom, and contains arguably the most noxious smell in nature. Amorphophallus titanum even has a great name. Meaning “giant misshapen phallus” in ancient Greek; the plant was given a more genteel common name, titan arum, by Sir David Attenborough. Nothing about the bloom’s fragrance is polite. Like many fly-pollinated plants, the flower is a carrion mimic, letting out an odor during the first few hours of opening that smells exactly like putrid meat.
Much sought after by rare tropical plant collectors, titan arum seldom blooms, but when it does, it usually causes quite a stir. The first specimen to bloom in the U.S, at the New York Botanical Garden in 1937, led to the adoption of the species as the official flower of the Bronx. The inflorescence is characteristic of others in the family, with a spathe, which resembles a single large petal (in this case a breathtaking purple and green) wrapped around a spadix of flowers, which resembles, apparently, a misshapen phallus. The spadix is topped by a large, creamy-white sterile appendage, with both male and female flowers borne near its base. The female flowers are receptive the night the structure opens and for the next few days, then they close and the male flowers above release their pollen. This prevents self-pollination as the blooms are visited by hundred of flesh flies and carrion beetles. After blooming, if pollination has not occurred, the entire inflorescence collapses.
Amorphophallus titanum is typically comprised of a single leaf, borne on a very tall stalk which resembles a palm tree drawn by Dr. Seuss. This leaf photosynthesizes for months, pumping starch into its underground corm. Once enough energy is stored in the corm, the leaf dies to the ground and the plant goes through a dormancy period. After a few months, a new leaf emerges. When it’s ready, Amorphophallus titanum puts out an inflorescence instead of a leaf. Our titan arums have bloomed several times in the past here at the Marie Selby Botanical Gardens, and this year we have a young specimen who felt ready. We are measuring the inflorescence’s progress as it grows. It won’t be long before the whole thing’s done, so be sure to get in this week to see it in the Tropical Conservatory.
Text by David Troxell