The leek is a well-known vegetable cultivated since the old times for its cylindrical and edible bulb formed in the base of the leaves. It is highly appreciated as seasoning for the flavour that confers to many dishes, although it is also consumed raw or in purées, soufflés or pies. The nutritious importance lies in the vitamins, minerals and the essential oil that leeks supply.

The leek is a very old vegetable that provides multiple medicinal benefits. It is used for its diuretic and antiseptic effect and it is suitable to treat various kidney ailments, as well as arthritis or rheumatism disorders.

The leek is a well-known vegetable cultivated since the old times for its cylindrical and edible bulb formed in the base of the leaves. It is highly appreciated as seasoning for the flavour that confers to many dishes, although it is also consumed raw or in purées, soufflés or pies. The nutritious importance lies in the vitamins, minerals and the essential oil that leeks supply.

Leeks belong to the same family as garlic and onions. Unlike these species, leeks develop a generally little widened bulb, although some varieties do not develop it. This bulb is formed in the base of the overlapped leaves, that acquire the characteristic white colour. The greater the white area is, the better their quality; the white part appears when the base of the leaves is deepened in the soil.

This species is well-known from very old, although its origin is not very clear. It is thought that it comes from the Eastern Mediterranean and the Near East, where it was already cultivated around 4000 years back. From there it spread to the rest of the world.

Leeks are part of many dishes in the high-class cooking and they are mainly used as seasoning. They have given rise, among other dishes, to the vichyssoise, a typical cold summer soup. It is also an ingredient for making soufflés, purees, pies and leek pastry. They can be consumed raw, as part of a salad. The green part is cooked to flavour stocks and stews.

The energetic value of leeks is very low, since it contains few proteins and lipids. This makes it suitable for slimming diets. However, it supplies minerals and vitamins; besides, it contains an essential oil that has beneficial effects for the digestive apparatus.

The leek belongs to the family of the Liliaceae, like the onion and the garlic. The species is Allium porrum. It is cultivated for the slender and white bulb formed in the base of the leaves, that is less developed than those of the other two species. It is a biennial plant, that is to say, it blooms during the second year.

This vegetable forms multiple white roots. The stem is placed on them forming a disc, as it happens with the garlic and the onion. On the stem the leaves are arranged forming the slender and white bulb. On the top, the leaves are flat and green, sometimes reaching up to 40-50cm high. They have a smoother and sweeter taste than onions.

During the second year, the plant bears the stem on which the flowers will develop, arranged in umbels of white or pink colour. The seeds are black, slightly rounded, although with flattened faces.

This plant is quite resistant to cold weather, although it prefers tempered and humid climates. It prefers deep, rich and fresh soils.