Dill is a short-lived annual herb, native to southwest and central Asia. It is the sole species of the genus Anethum, though classified by some botanists in the related genus Peucedanum as Peucedanum graveolens (L.) C.B.Clarke. Dill leaves must be used fresh, as they lose their flavour rapidly if dried; even freeze-dried dill leaves have very little flavour. It is thus necessary to grow a supply of plants, rather than store the leaves.