About two hundred species of tuberous plants belong to the genus amorphophallus, widespread in Africa and Asia, particularly in the tropical or subtropical areas. The tubers are generally large, round or elongated; in spring, from the tuber, a short, squat trunk rises, which carries 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 spats surround the spadix; the spadix can be yellow, green, pink or purple, and bears both female flowers, male flowers and small sterile flowers. The spates are greenish, purple or orange in color, have a velvety and moist appearance and are furrowed by numerous veins. The flowers of amorphophallo give off a foul odor, similar to that of rotting flesh, which attracts flies and other pollinating insects.
After flowering from the stem, a single large leaf is produced, which resembles palm fronds: the leaf withers in autumn, when the plant enters 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 tubers of amorphophallo are used for food, cooked. The tubers are also used in medicine and in herbal medicine, from them glucomannan is extracted, a dietary fiber used in cases of dyspepsia or obesity.
The Amorphophallus konjac deserves a special mention, a plant cultivated in Asia and in particular in Japan, China and Korea, from which we obtain an alimentary gelatin widely used in the Asian world but not only.
The Amorphophallus prefers semi-shady locations, in places sheltered from the wind. Usually they fear the cold, but they can also be grown outdoors in place with mild winters and low rainfall during the cold season.
it begins to water as soon as the tuber shows the first shoots, the watering should be administered only when the ground is well dry, avoiding excesses. When the leaf is produced, provide fertilizer for plants see, every 10-15 days, mixed with the water of the waterings. When the leaf withers it is good to avoid watering until the following spring. During the cold months it is possible to dig up the tuber and store it in a dry, temperate and oxen place, until the following spring.
These plants prefer very rich and soft soils, consisting of peat, mature manure and little sand, to increase drainage. They can be cultivated in pots, providing a container that has a diameter equal to three times that of the tuber; after flowering, compact the soil around the tuber; remember to repot potted plants every 2-3 years
The multiplication of the Amorphophallus can generally take place by seed, or by division of the tubers.
Amorphophallus: Pests and diseases
often some species of lepidoptera choose the tubers of amorphophallo to lay their eggs, the larvae will use the pulp of the tubers to eat them. Excessive watering can favor the development of tubers rotting.