[1] This plant grows in wet habitat such as swamps and lakeshores, sometimes in the water.

It is a perennial herb with a hollow, grooved stem up to 2 meters tall.

The leaves are up to 30 centimeters long with blades borne on hollow petioles that clasp the stem at their bases.

[3] When eaten by dairy cows, the plant tends to imbue their milk with an unpleasant taste.

[3] The rootstock is acrid and poisonous, but the leaves have been cooked and eaten as a vegetable in Italy and the ripe seeds - which are aromatic due to their limonene content - have been used (in small quantities) as a spice or seasoning in Scandinavian cuisine.