What’s Fresh in February? Leeks

Savor the unsung hero of the winter kitchen.

Story By Bailey Gilliam

We’ve all heard of potato leek soup, but few stop to ponder the humble vegetable paired so often with the potato. Leeks are alliums, which means they are related to garlic, chives, shallots and onions. But they are quite a bit more versatile than the average onion-y produce. They add a sweet, mild onion flavor to many dishes and can be enjoyed alone. Keep reading to learn the ins and outs of this underrated onion relative.

Health benefits

Leeks are low in calories, much like green onions, and boast many health benefits. They’re rich in flavonoids and antioxidants, with inflammatory, anti-diabetic and anticancer properties. They’re a good source of vitamin K, which may help reduce the risk of osteoporosis, aiding in blood clotting for wounds and supporting heart health. They’re high in fiber, which helps promote regularity and a healthy digestive system. They are also a good source of folate and B6, which work to keep homocysteine levels low, preventing artery damage and reducing the formation of blood clots.

Add it to your garden

Plant leeks in a spot with full sun (at least 8 hours a day) and deep, fertile, well-drained soil. They can be bought from a garden center or greenhouse as young plants or started from seed easily at home. They are cool-weather tolerant and can be planted before the last frost. Be sure to plant them deeply to encourage long stalks, and then mulch them to keep the soil from drying out. Leeks have shallow root systems and will need regular watering. About an inch per week is sufficient; however, give them a drink if the top 2-3 inches are dry. Leeks planted in sandy soil (which is likely here) will need more water. Luckily, leeks will be perfectly happy to sit in your garden and do their thing. Unlike other crops, which must be harvested all at once and stored, you can snag half a dozen leeks whenever you need them from late summer until the ground freezes. But if you’re not ready for a gardening commitment just yet, pick up some leeks at the Farmers Market of Bluffton from noon to 5 p.m., Thursdays in Old Town Bluffton. 

Recommended varieties

There are many varieties of this allium out there, but here are a few of our favorites:

Tadorna: A vigorous grower with dark green-blue foliage that will overwinter in mild climates.

King Richard: A large leek with shanks that can reach a foot long; it can tolerate fall temperatures as low as 20 degrees and matures early at just 75 days.

Dawn Giant: Lives up to its name, with a 15-inch shank reaching 2 inches in diameter.

Leeks vs. scallions

While leeks and scallions may appear similar with the same shape and ombré effect of pale green root ends intensifying into dark green tops, they have plenty of differences worth distinguishing. They are related to one another but should not be used interchangeably. The entire stalk of the green onion is typically sliced and eaten raw because of its delicate texture and flavor. Leeks, on the other hand, are tougher than green onions and aren’t commonly eaten raw. Both green onions and leeks soften when cooked, but leeks take a little longer to get there. Leeks are larger and thicker and sold in single stalks, whereas scallions are sold in bunches. Once cooked, leeks have such a beautifully subtle flavor that some would have difficulty distinguishing leeks from the onion family. In contrast, green onions maintain their signature sharpness, so it’s important to tell them apart. 

How to pick

When shopping in a grocery store or farmers market, choose straight and firm leeks with bright green leaves. Because you’ll typically use only the white and light green parts for cooking, look for leeks with plenty of white coming up from the root. Also, keep in mind that smaller leaks tend to be more flavorful. 

Store it

Leeks can keep for up to two weeks when loosely wrapped in plastic and kept in the fridge. Wait to wash or trim them until you’re ready to use, as this can help prevent their odor from being absorbed by neighboring foods. You also can freeze leeks in two different ways: cooked and raw. If you’re saving a stash of leek tops for stock in a few weeks, freeze them after thoroughly washing them. If you want to freeze the white part, cut and sauté it before freezing.

Cut it out

How you cut leeks will vary based on how you cook them. But this is the basic way to cut them. Chop off the stringy roots and dark green leaves. You won’t use the tough tops in most leek recipes, but you can save them for vegetable stock. Slice the leeks in half lengthwise. Lay them cut-side-down on a cutting board and cut them into thin half-moons. Transfer to a colander and rinse under cool running water, tossing to remove dirt or debris. Use a kitchen towel to blot them dry before cooking.

Cooking tips

Leeks are incredibly versatile and have endless culinary possibilities. Typically, their white root ends are sliced up and pureed into soup, roasted or sautéed, while their tougher dark green ends can be added whole to stews or stocks for extra aromatic flavor. Follow these cooking guidelines for delicious leeks: 

Grill: Slice in half lengthwise, rinse and dry well, drizzle with olive oil and grill on both sides on medium-high heat until they’re well charred and tender. Season with salt and pepper. 

Roast: Chop into 1-inch chunks, toss with olive oil, salt and pepper and roast at 425 degrees for 15-20 minutes or until tender. 

Sauté: Heat olive oil in a large skillet over medium heat. Add the leeks and a few pinches of salt and pepper and cook, stirring occasionally, until they soften, about 5 minutes. 

Potato leek soup

Ingredients

3 tablespoons unsalted butter

4 large leeks, white and light green parts only, roughly chopped (about 5 cups)

3 cloves garlic, peeled and smashed

2 pounds Yukon Gold potatoes, peeled and roughly chopped into 1/2-inch pieces

7 cups chicken or vegetable broth

2 bay leaves

3 sprigs fresh thyme

1 teaspoon salt

1/4 teaspoon ground black pepper

1 cup heavy cream

Chives, finely chopped, for serving

Directions

[1] Melt the butter in a large soup pot over medium heat. Add the leeks and garlic and cook, stirring regularly, until soft and wilted, about 10 minutes. Adjust the heat as necessary so as not to brown. [2] Add the potatoes, broth, bay leaves, thyme, salt and pepper to the pot and boil. Cover and turn the heat down to low. Simmer for 15 minutes or until the potatoes are very soft. [3] Fish out the thyme sprig and bay leaves, then purée the soup with a hand-held immersion blender until smooth or with a standard blender in batches. [4] Add the heavy cream and bring to a simmer. Taste and adjust the seasoning with salt and pepper. If the soup is too thin, simmer until thickened. If it’s too thick, add water or stock to thin it out. Garnish with fresh herbs if desired.

Smoked Gouda and leek tart

Ingredients

Flour, for dusting

1 sheet puff pastry

2 small leeks (white and light green parts only), well rinsed, dried and thinly sliced (about 2 1/2 cups)

1/2 cup coarsely grated smoked Gouda cheese

1/4 cup freshly and finely grated Parmesan cheese

Kosher salt and freshly ground black pepper

2 tablespoons finely chopped chives

Directions

[1] Heat the oven to 400 degrees. On a lightly floured surface, roll the puff pastry and transfer to a parchment-lined baking sheet or pie pan. Prick the pastry with a fork and scatter with the leeks and both cheeses. Sprinkle with a pinch of kosher salt and 1/4 teaspoon pepper. [2] Bake until the pastry is a deep golden brown and the leeks are tender, 25 to 30 minutes. Cool for 10 minutes. Garnish with the chopped chives, cut and serve.