• A hardy herbaceous perennial, Sium sisarum, growing to 1 m with small clusters of tiny fragrant flowers, narrow leaves and aromatic tuberous roots. The young shoots may be steamed or stir-fried. The roots, which should be cooked in their skins to preserve the flavour, are steamed, boiled or pickled and are eaten in Germany with new potatoes. The hard inner core of the root is removed.