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Healthy and Sustainable Food

Leeks

DATES AVAILABLE:

New England: Mid-July through late November; Storage: 1-3 months
Mid-Atlantic: July through late November; Storage: 1-3 months

The leek season may continue intermittently through March since some varieties can survive the alternating freezes and thaws of winter and can be dug in early spring whenever the ground thaws.

BRIEF DESCRIPTION:

The garden leek (Allium porrum, Liliaceae) is a member of the lily family as are onions, shallots, scallions and garlic. They were prized in ancient Egypt and after introduction in Europe became the national emblem of Wales where they thrived in the cold weather. They are known to have been cultivated in the United States since the late 1700s. The leek’s white root, cylindrical like the scallion, can grow to 12” in length and 2” in diameter. The leek maintains this cylindrical shape throughout the neck of the plant, changing from white to light green; ending in dark green, tightly wrapped flat leaves that form V-shapes as they continue to the top. Cultivation produces larger leeks, but the smaller wild ones have a more intense flavor.

VARIETIES:

“Tornado” has dark blue-green leaves and a white, medium shaft. “King Richard” has a long slender shaft and is finely textured. Although “King Sieg” has a medium length shaft, it is 3” thick producing more edible leek.

USING LEEKS:

Select leeks that are straight, firm and uniform. Leaves should be bright green at the top and no cracks or bruises should be visible. Bulbous formation of the neck and wilted leaves are a sign of age. Larger leeks are older and more fibrous, younger leeks are sweeter and more tender. Squeeze the neck gently and avoid if a hard stalk (a sign of age) is felt. Choose leeks with diameters of no more than 1 to 1.5” for tenderness.

Before use, trim the about ¼” from the root end and remove the outer layer. Cut off most of the tough leaves, leaving about 2” of dark green. If desired, the trimmed ends can be reserved for use in stock. Leeks are grown in sandy dirt and due to the tight wrapping of the layers, leeks contain a fair amount of sediment. If using the leeks whole, slice lengthwise but leave part of the leek attached, open, and run under water to remove the dirt and sand. If using sliced rounds of leeks, soak them in water or hold under running water to remove any sediment.

The necks of young leeks can be sliced and eaten raw in salads. Leeks can also be cooked in a variety of ways, including boiling, baking, steaming, sautéing, and roasting. They can also be added to soups, casseroles, savory pies, egg dishes, and pasta.

Leeks are much sweeter and more subtle than onions and also have a milder aroma. If cooking the leeks whole, choose stalks with uniform diameters for even cooking times.

NUTRITIONAL INFORMATION:

One cup of leeks has only 54 calories, but is rich in beta-carotene, vitamin K, and manganese. They are also a good source of iron, folate, and vitamin C, and provide 2 g of fiber in each serving.

STORAGE INFORMATION:

General: Store leeks in the refrigerator unwashed, untrimmed, and loosely wrapped in plastic for one to two weeks. Although much less pungent than onions, leeks still have an odor that can affect other foods they are stored with; plastic helps to contain this smell.  Cooked leeks can only be kept refrigerated for up to two days. 

Freezing: Leeks can be frozen, but only if using in soup or stew as they become mushy and bitter. To freeze, steam or boil leeks for two to three minutes, chill, and seal in an airtight container.  Do not defrost before use, but add frozen leeks directly to the recipe.