How to Grow Leeks:
Plant, Hill, and Harvest All Winter

Leeks growing in the vegetable garden.

Learning how to grow leeks is easy, and they reward you with a mild, sweet onion flavor long after the rest of the garden is done. Leeks take their time, but they can stand in the ground and be dug as you need them, right through the winter in many areas.

This guide covers it all: starting seeds, planting deep, hilling, harvesting, storing, and our favorite winter leek soup.

From My Garden

We have grown leeks in our garden several times. They are easy to grow, and they can be left in the ground and harvested all winter.

One of our favorite winter soups is a hearty leek soup with ground beef, from our friend Norman in Northern Germany. He even sent me pictures of how to make it! It is so delicious that I plan to make it every week or two during the winter months. The recipe is below.

Charlotte

When should you start leeks?

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Leeks at a Glance

Factor	Guideline
Type	Cool-season; a biennial grown as an annual, in the onion family
Sun	Full sun
Soil	Rich, loose, well-drained; pH 6.0 to 6.8
Start seeds	Indoors 8 to 10 weeks before your last spring frost
Plant out	Around the last frost, when seedlings are pencil-thick
Spacing	6 inches apart, rows 12 to 18 inches apart
Days to harvest	About 100 to 150 days from transplant, depending on the variety
Harvest	When stems are 1 to 2 inches thick; many varieties hold in the ground all winter

Close-up of healthy leek plants in the garden — Healthy leek plants.

Leek Varieties

Leeks come in two main kinds: quick summer leeks with longer, thinner stems, and hardy winter leeks with thicker stems and blue-green leaves that stand up to cold. Choosing the right kind is the first step in how to grow leeks for your season.

Early or summer leeks: King Richard is a quick, tall leek for summer and fall harvest.
Winter leeks: American Flag, Giant Musselburgh, and St. Victor are hardy varieties to leave in the ground for winter harvest.
Others to try: Carina, Durabel, Laura, and Splendid.

Leeks are related to onions, garlic, and shallots, but instead of a bulb they grow a long, thick stem, with flat, strap-like leaves. See our guide to growing onions for the rest of the family.

How to Plant Leeks

Young leek plants growing in the garden — Young leeks.

Start from seed indoors

Sow seeds about 1/4 inch deep in flats of loose seed-starting mix, 8 to 10 weeks before your last spring frost. They sprout in 10 days to 2 weeks. Trim the tops back to about 4 inches if they get floppy; it makes sturdier plants. Starting from seed is the usual way to learn how to grow leeks, though many nurseries also sell young leek plants in spring.

Or sow outdoors

In mild areas, sow seeds outdoors in early spring, 1/4 to 1/2 inch deep, and thin to 6 inches apart. Leek seedlings look a lot like grass, so be careful not to weed them out!

Plant deep for long white stems

Set transplants out when they are about pencil-thick, around your last frost date. Dig a trench about 6 inches deep, or poke 6-inch holes with a stick or dibble, and drop one seedling into each so only the top few inches show. Water them in gently and let the soil fill in over time.

Give leeks rich soil and full sun. Work in plenty of compost or well-rotted manure, and keep the pH between 6.0 and 6.8. In the Northern Hemisphere, leeks are planted in spring; in reverse-season climates, plant in late autumn.

Caring for Leeks

Leeks growing in the ground in the vegetable garden — Leeks growing in the garden.

Water: Leeks have shallow roots. Keep the soil evenly moist, about an inch of water a week, and water when the top inch is dry.
Hill them: As the leeks grow, pull soil up around the stems a few inches at a time. Covering the stem keeps it white and tender, called blanching. Stop at the point where the leaves branch, so soil doesn't get inside the leaves.
Feed: Side-dress with compost or a balanced fertilizer once or twice in summer.
Weed: Leeks don't like competition. Mulch with straw or shredded leaves to keep weeds down.

Don't want to bother with hilling? Many gardeners skip it. The green part of the stem is just as tender as the white; only the color is different. Unhilled leeks are also easier to wash. That makes learning how to grow leeks even simpler.

Good companions are carrots, celery, lettuce, and strawberries. Keep leeks away from beans and peas. See our companion planting chart.

Harvesting Leeks

Harvest leeks when the stems are 1 to 2 inches thick. Loosen the soil beside each one with a garden fork and lift it gently; pulling can snap the stem. Harvest is the easy, happy end of how to grow leeks.

Leeks are patient. They lose little flavor or texture waiting in the ground, so dig them as you need them, from late summer through winter. Hardy winter varieties stand up to frost. In colder areas, cover the row with a thick layer of straw to keep the ground from freezing, or harvest before the ground freezes hard.

For a longer harvest, plant a few batches about three weeks apart.

Grow a second harvest

Dig a summer leek with a good part of its roots, trim the stem about an inch above the roots, and replant it with about half of the stub above the ground. Water well. In a week or so, new stems begin to grow. The second leeks are smaller, but perfect for a fall salad or a pot of soup. It even works with store-bought leeks, as long as the roots are still white and plump.

Cleaning, Storing, and Freezing Leeks

Harvested and cleaned leeks from the garden — Harvested and cleaned leeks.

Soil hides between the layers, so wash leeks well. Trim the roots and the tough dark tops, slice the leek in half the long way, and rinse it under running water while fanning the layers. Or slice it first and swish the pieces in a bowl of water; the soil sinks and the leeks float. Once you know how to grow leeks, cleaning them well is the next skill to learn.

Fresh leeks keep 1 to 2 weeks in a bag in the refrigerator. For longer storage, freeze them: pack cleaned, chopped leeks in 1-cup portions, or freeze them in ice cube trays (each cube is about 1 tablespoon), then bag the cubes.

In the kitchen, leeks are the sweetest and mildest of the onion family. They are wonderful with potatoes, and they are the main ingredient in vichyssoise, a creamy cold summer soup. See how to freeze vegetables for more.

Sliced fresh leeks from the garden — Fresh sliced leeks, ready for the pot.

Norman's Cheese and Leek Soup with Ground Beef

Pot of homemade cheese and leek soup with ground beef — Cheese and leek soup with ground beef: a winter favorite.

A hearty winter soup from our friend Norman in Northern Germany · Serves about 4

Ingredients

Ingredient	US measure	Metric (Norman's recipe)
Onion	1 medium	1
Garlic	1 clove	1 clove
Leeks	2 medium	2
Ground beef	1 pound	500 g
Sunflower oil (or other cooking oil)	2 tablespoons	2 tbsp
Salt	to taste	to taste
Vegetable broth	3 1/3 cups	800 ml
Processed cheese, cream variety (or cream cheese)	7 ounces (a scant 1 cup)	200 g
Crème fraîche (or sour cream mixed with heavy whipping cream)	2/3 cup (5 ounces)	150 g
Black pepper	1 pinch	1 pinch
Grated nutmeg	1 pinch	1 pinch

US measures are rounded for easy cooking. If you have a kitchen scale, Norman's metric amounts are exact.

Directions

Prepare the vegetables. Peel and finely dice the onion and garlic. Halve the leeks lengthwise, wash them well, drain, trim, and slice.
Cook the leeks. Sauté the leeks in a large pot until tender, being careful not to let them burn. Even a little scorching changes the flavor of the whole soup.
Simmer. Pour in the vegetable broth and simmer gently for about 10 minutes, stirring now and then.
Brown the meat. Meanwhile, brown the ground beef with the diced onion and garlic in a pan with the oil.
Finish the soup. After 10 minutes, stir the processed cheese, crème fraîche, and browned meat into the leek broth. Bring to a boil, and season to taste with salt, pepper, and nutmeg.
Serve with a baguette fresh from the oven, if you like. Guten Appetit!

Step by step

Sliced leeks in a pot and ground beef in a frying pan, with cheese and cream

1. Sliced leeks in the pot, ground beef in the pan.

Sautéed leeks in a pot and browned ground beef in a pan

2. Leeks sautéed until tender; beef browned with onion and garlic.

Leeks simmering in vegetable broth in a covered pot

3. Leeks simmering in the broth.

Processed cheese and cream stirred into the leek broth

4. Cheese and cream stirred in.

Browned ground beef added to the creamy leek soup

5. The browned beef goes in.

Finished cheese and leek soup with ground beef

6. Bring to a boil, season, and serve!

Charlotte's Kitchen Notes

Don't scorch the leeks! Norman really means it when he says to be careful when you sauté them. One time I scorched just a few of them a little bit, and it completely changed the flavor of the soup. Keep the heat moderate and stir often.

Cheese: I use cream cheese for the processed cheese.

Crème fraîche: I use a mix of sour cream and heavy whipping cream instead.

I have a kitchen scale, so I follow Norman's metric amounts.