Prefers a cool peaty soil in the bog garden, woodland garden or a sheltered border in semi-shade. Prefers a loamy or peaty soil and will tolerate a sunny position if the soil is moist but not water-logged and the position is not too hot or exposed. Tubers should be planted about 10cm deep. Only plant out full sized tubers and mulch them with organic matter in the winter. Plants need protection from slugs. Most species in this genus are dioecious, but they are sometimes monoecious and can also change sex from year to year.

Tuber - it must be thoroughly dried or cooked before being eaten. The roots can be cut into very thin slices and allowed to dry for several months, after which they are eaten like potato chips, crumbled to make a cereal or ground into a cocoa-flavored powder for making biscuits, cakes etc. They can also be pounded into a powder, this is thern left to dry for several weeks when it becomes safe to use. The root is up to 5cm long and 2cm wide. Caution is advised, see the notes above on toxicity.

Seed - best sown as soon as it is ripe in a shady position in a cold frame. Stored seed remains viable for at least a year and can be sown in spring in the greenhouse but it will probably require a period of cold stratification. Germination usually takes place in 1 - 6 months at 15°c. When large enough to handle, prick the seedlings out into individual pots and grow them on in light shade in the greenhouse for at least a coupe of years until the corms are more than 20mm in diameter. Plant out into their permanent positions whilst they are dormant. Division of tubers when the plant dies down in late summer.

Wet woods, bogs and swamps.