The leek is a biennial herbaceous vegetable plant 20 to 90 cm high, cultivated for its leaves (pseudo-stems) eaten as vegetables.
Its elongated, lanceolate, opposite, flat, dark green or yellowish green sheathing leaves are in the form of bands or ribbons streaked with parallel veins.
The base of the leaves forms a pseudo-stem called a “barrel”, the buried part of which is white.
The flowers, greenish white, appear clustered in an umbel at the top of an erect flower stalk in the second year.