The titan arum (Amorphophallus titanum) is a plant with the largest flowering structure in the world. Its inflorescence is made up of many tiny flowers on a spadix, surrounded by a spathe, both types of spikes, making it resemble the related calla lily in shape. Titan arum can reach nearly ten feet (3 m) in height. It is native to the Sumatran rainforests in Indonesia but has been cultivated elsewhere. Titan arum was discovered by Italian botanist Odoardo Beccari in 1878.
Titan arum has a hollow spadix ranging from pale yellow to light purple. The upper, visible portion is covered in pollen, while the lower part is covered in bright orange carpels, the female reproductive organ. The spathe is green on the outside and reddish-purple on the inside. Titan arum is one of the plants nicknamed "corpse flower," as it emits a smell of rotting meat to attract its fly and beetle pollinators. The dark red color of the plant also simulates dead flesh, and the tip of the spadix is close to human body temperature when it blooms, further attracting carrion insects.
Male and female flowers bloom in the same inflorescence of the titan arum. Male flowers bloom a day or two after female flowers to prevent self-pollination. After blooming, the flowering structure wilts and dies within a few days.
A single huge, umbrella-like leaf sprouts from the plant's root after the flower has died. It can reach up to 20 feet (6 m) in height, with a 16 foot (5 m) span. The leaves of titan arum plants in captivity only grow to about 12 feet (3.6 m). The leaf is replaced every year until the plant has stored enough energy to bloom again. At that point, the plant becomes dormant for four months before blooming again.
Titan arum plants were first cultivated in captivity in the Royal Botanic Gardens at Kew in London, in 1889. Since then about 100 plants have been cultivated, including some in the United States and Germany.