Michigan Fresh: Leeks (HNI51)
Using, Storing and Preserving Leeks
The leek is a member of the onion family, although it does not form a bulb. Leeks have a bundle of leaf sheaths that are sometimes referred to as a stalk or stem. It resembles an overgrown green onion. The leek has leaves similar to those of the garlic plant—flat rather than round. Both the leaves and stems of the leek plant may be eaten. They have a mild onion-like flavor and are often used to flavor soups or dried and added to herb mixtures.
Leeks can be grown from seeds or transplanted as onions are. Because of their long growing season—70 to 120 days—they are more often planted as seedlings than grown from seeds. They are cold-tolerant and can be put in the ground before the last frost. They are available in the market year round but are at their peak from September through April.
Leeks are low in sodium and calories. They are also a significant source of vitamins B6 and C, folic acid and iron.
Select leeks that are free from blemishes. The tops should be bright-colored and fresh-looking, not dry, and free of discoloration.
Leeks are divided into summer leeks and overwintering leeks. Summer leeks are harvested in the season when they were planted; overwintering leeks are harvested in the following summer. Summer leeks are generally smaller, and the overwintering leeks are stronger flavored.
- Varna—an early-season variety that produces clumps of slender plants.
- King Richard—a summer leek with long, slender stems. It produces a sweet, tender product that stays white all summer long. It is best used for soups and salads.
- Columbus—an early-season variety producing medium-sized leeks with blue-green leaves.
- Rival—another early-season variety that can grow up to 36 inches tall with a diameter of 2 inches and has green leaves.
- Lancelot—grows a short leek with a large, cylindrical stalk and greenish gray leaves. It is frost-resistant.
- Jolant—a winter-hardy variety with medium-sized stalks and blue-green leaves.
- Splendid—a rapidly growing variety that produces 7- to 8-inch, medium green stalks.
- Albinstar Baby Leeks—a Dutch variety that was developed for its small size product. It is typically harvested when it is only ½ inch in diameter.
- Otina – a late-season variety from France. It is mild-flavored with green-blue leaves.
- Durabel—a thick winter leek with mild flavor and tender texture.
- American Flag—an overwintering variety with a mild, sweet, onion-like flavor. This variety is very much like an overgrown scallion.
- Bandit—a short, sweet leek that grows thick. The leaves are blue-green, and the plant is winter-hardy.
- Giant Musselburg—a variety of leek with large, white, tender stalks, medium to dark green tops and a mild flavor. It is very hardy.
Storage and food safety
The interlacing leaves make leeks a difficult vegetable to clean thoroughly before preparation. Be sure to rinse with lots of fresh running water to remove the grit found between the leaves. After washing, leeks can be eaten raw or cooked. Cooking times will vary with the diameter of the leek. Leeks are generally considered sufficiently cooked when the stalk can be easily pierced with a fork. Avoid overcooking —this makes leeks tough. Leeks are commonly used in soups and stews but are also gaining popularity as a vegetable that can stand alone—steamed, sautéed or served with a creamed sauce.
Leeks can give off an odor that can be absorbed by other foods in the refrigerator. Therefore, wrap leeks in plastic when storing in the refrigerator. Do not trim or wash before storing. Leeks will last up to two weeks in the refrigerator if they are purchased fresh. Once cooked, leeks can be kept in the refrigerator and used within two days.
Leeks do not freeze well. They develop a strong, bitter flavor. Freezing also makes leeks mushy. They also are not good candidates for canning because the high heat of pressure canning turns the product to mush. They can be dried. Wash well and cut in ¼-inch slices. Dry at 145 degrees F. until crisp.
- Leeks. 2009. Texas AgriLife Extension Service.
- Andress, Elizabeth L., and Judy A. Harrison. 2006. So Easy to Preserve (fifth edition). The University of Georgia Cooperative Extension Service.
- MacKenzie, Jill. 2008. Leeks. University of Minnesota Extension.
Prepared by: Robin Danto, MSU Extension educator