The 'Japanese Mountain Yam' or 'Yamaimo' forms an herbaceous climber, sending twining shoots to 3m high each year with highly attractive heart shaped leaves with long drip tips. The large (30 to 90cm long) tuber is edible and widely used culinarily in Asia as a carbohydrate and is unusual for a yam in that it can apparently be eaten raw. Edible arial tuberlets form on the stems and make a ready means of increase. Very hardy once established, this is best in fertile open textured soil, not too dry, in sun or semi-shade.