Amorphophallus titanum is incredible — its amazing size and equally breathtaking smell have earned it celebrity status in the plant world. The genus name Amorphophallus is derived from Greek and means “shapeless or deformed phallus”, and the species name titanum means “extremely large”.
The titan arum has the distinction of being the largest unbranched inflorescence in the world. It is found in the forests of Sumatra, an island in Western Indonesia. The first European to collect seeds of this plant was an Italian botanist named Odoardo Beccari, who visited Sumatra in 1878.
Seeds collected by Beccari were germinated in Italy, and one plant made its way to The Royal Botanic Gardens, Kew in England — it was here that the first Amorphophallus titanum in cultivation bloomed in 1889.
The humongous inflorescence is composed of a spadix (a thick spike covered in small flowers) and a spathe (a showy bract that encloses the spadix). This flower structure is typical of the Araceae. The combined spadix and spathe can reach over 1m across. The spadix itself can reach 3m in height, and emits a most incredible odor — often compared to rotten meat and excrement. The spathe is ruffled and meaty red in colour.
Studies have shown that the inflorescence also generates heat during flowering. This combination of odor, colour and heat effectively imitates a decomposing mammal, earning the plant the common name of carrion flower or corpse flower. The potent smell is believed to attract pollinators over the long distances that separate these rare flowers (watch a video explaining the inflorescence and pollination).
A massive tuber sustains the inflorescence, and can weigh between 50 and 90kg (100-200lbs!) Once flowering is finished, the plant dies back to the large underground storage organ. After a resting period, a giant compound leaf is produced which resembles a small tree and can measure 6m tall and up to 5m across. The leaf is photosynthetic and restores energy to the tuber. There may be a gap of several years in which the plant produces only leaves before the next flowering stage occurs. The University of Wisconsin-Madison Botany Greenhouses and Botanical Garden provide a nice illustration of the lifecycle.
Photography resource link (added by Daniel): the Tao of Photography weblog by Andy Ilachinski (do be sure to browse through his recent portfolios via the right-hand sidebar).