{| border="1" cellspacing="0" align="right" cellpadding="2" ! align="center" bgcolor=lightgreen | Leek |- || |- ! align="center" bgcolor=lightgreen | Scientific classification |- | {| align="center" | align=left | Kingdom: || Plantae |- || Division: || Magnoliophyta |- || Class: || Liliopsida |- || Order: || Asparagales |- || Family: || Alliaceae |- || Genus: || Allium |- || Species: || ampeloprasum |} |- ! align="center" bgcolor="lightgreen" | Binomial name |- | align="center" | Allium ampeloprasum var. porrum (L.) J. Gay |- |} The Leek (Allium ampeloprasum var. porrum (L.) J. Gay) is a vegetable belonging, with onion and garlic, to the Alliaceae, the onion family. Also in this species are two very different vegetables: The elephant garlic (Allium ampeloprasum var. ampeloprasum) grown for its bulbs, and kurrat which is grown for its leaves in Egypt and elsewhere in the Middle East.

Rather than forming a tight bulb such as the onion, the leek produces a long cylinder of bundled leaf sheaths which are generally blanched by pushing soil around them (trenching). They are generally considered to have a finer flavor than the common onion. They are often sold as small seedlings in flats which are started early in [greenhouse]]s, to be set out as weather permits. Once established in the garden, leeks are hardy and can be left in the ground during the winter to be harvested as needed.

Leeks are an essential ingredient of cock-a-leekie soup.

Leeks were prized by the Egyptians, the Greeks, and the Romans who distributed it all over Europe. It is a national emblem of Wales.

See also: List of vegetables