About two hundred species of tuberous plants belong to the genus amorphophallus, widespread in Africa and Asia, in particular in tropical or subtropical areas. The tubers are generally large, round or elongated; in spring a short stocky stem rises from the tuber, carrying a long spadix in the shape of a cone or spear, which can have various sizes, from 40-50 cm, up to three meters of the Amorphophallus titanum; one or more spathe surround the spadix; the spadix can be yellow, green, pink or purple, and bears both female and male flowers and small sterile flowers. The spathe are greenish, purple or orange in color, have a velvety and moist appearance and are furrowed by numerous veins. The amorphophallo flowers give off a disgusting smell, similar to that of rotting meat, which attracts flies and other pollinating insects.
After flowering, a single large leaf is produced from the stem, reminiscent of palm fronds: the leaf withers in autumn, when the plant goes into vegetative rest. Amorphophallus titanum produces the largest inflorescence in the world, and has produced its large flowers even in cultivated specimens. In the places of origin the amorphophallo tubers are used for feeding, cooked. The tubers are also used in medicine and herbal medicine, from which glucomannan is extracted, a dietary fiber used in cases of dyspepsia or obesity.
A particular mention deserves the Amorphophallus konjac, a plant cultivated in Asia and in particular in Japan, China and Korea, from which we obtain a food gelatin widely used in the Asian world but not only.
The Amorphophallus prefers semi-shaded positions, in a place sheltered from the wind. They generally fear the cold, but can also be grown outdoors in a place with mild winters and low rainfall during the cold season.