Quick growing tuberous plants from Northern China. Above ground the foliage resembles mint and forms a good ground cover, whilst below ground numerous small knobbly tubers are formed. These can be harvested in late autumn once the foligae dies down. They can be eaten raw, tasting crisp and sweet rather like a water chestnut. Cooked they become more starchy, tasting more like a slightly nutty potato. in France they are known as crosnes and are braised in herbs and butter. 9cm pot.