How to Grow Leeks

Leeks are a cold-weather crop, but there’s no need to pull them when it gets warm out: letting them go to seed allows them to reseed themselves for the fall, plus the pollinators and predatory insects love their flowers. They are really cool looking, too. 

Botanical Information


  • Allium ampeloprasum


  • Leeks originated in the Mediterranean basin and are one of the oldest cultivated vegetables  FV
  • Egyptians used them as currency, along with oxen and beer FV
  • They are an important ingredient in many Asian cuisines, especially kimchi FV
  • Nero, the tyrannical Roman emperor, loved leeks; he believed they’d improve his singing voice; he ate them in soups and prepared in oil; he was called by some Porophagus, the leek eater FV
  • Leeks are included in illustrated carvings and drawings in Egypt and Mesopotamia, dating back to the second millennium BCE SSE
  • the leek is also a national emblem of the Welsh and in Henry V, Shakespeare notes the custom of wearing a leek to identify themselves is an ancient tradition for Welshman SSE

Physical Description

  • hardy biennial

Varieties & Cultivars

Categories or Types of Leeks

Colors Available

Varieties to Grow

Growth Requirements

Climate & Temperature Requirements

Air Temperature

Soil Temperature


Day Length or Light Requirements

Site Conditions Favored

Soil Requirements

Soil Texture

  • prefers loamy soil SoC


Nutrient Requirements

  • prefers rich, loamy soil enriched with mature compost SoC


Methods of propagation


  • Timing:
    • Indoors:
      • mid- to late-winter SSE
      • 6-8 weeks before early spring SoC
    • Outdoors:
      • early spring (cool soil) SoC
  • Depth:
    • plant seeds 1/4″ deep SSE
  • Temperature:
    • 55-85°F
  •  Fertilization:
    • fertilize seedlings when 2-3″ tall SSE
  • Spacing:
    • if starting outdoors, space them 1″ apart SSE
  • Germination:
    • 5-7 days SSE
    • 4-12 days SoC
    • 7-14 days SoC



Transplanting or Potting Up

Seed Saving

Planting Out

  • can be planted out 1-2 weeks after all danger of frost has passed SSE

Bed Prep & Soil Amendments

  • make sure the soil is well-fertilized as this crop is a heavy feeder; consider adding compost to the soil the year before you plant SSE

Bed Spacing

  • plant leeks 6″ apart SSE
  • plant leeks 4-8″ apart SoC

Row Spacing

  • 12-24″ apart SSE

Planting Depth

  • plant deep enough so that 1-3″ of the plant are above the soil SSE

Alternative Bed Methods

Container Gardening

Routine Cultivation & Maintenance

Water Requirements

  • keep well-watered through maturity, allowing soil surface to dry between waterings Soc
  • leeks need ample water SoC

Fertilization Recommendations

  • leeks may require regular applications of fertilizer SSE

Mulching & Weeding

  • mulching the soil around leeks can help protect the plant and keep roots cool and moist SSE
  • mulch to conserve soil moisture and control weeds SoC


  • as leeks grow, pile soil up around their base to make the white shaft longer; the soil blanches the new growth and it will just grow taller

Pinching or Pruning & Dividing



  • a deep mulch will allow harvest to continue until a hard freeze SoC

Companion Planting

Helpful Companions

Harmful Companions

Companion to..

Pests, Diseases & Problems

Common Pests

Common Diseases


Whole Plant






Harvesting & Storage

Edible Parts of the Plant

  • the white shaft of the leek, including the light green zone, is primarily what is used in cooking
  • the dark green leaves, while fibrous and inedible when fresh, turn into a fantastic spice when dried and ground to a powder (Here’s the recipe to dry leek greens or tops)


Days to Harvest / Harvest Timing

Freshly harvested leeks

Freshly harvested leeks

  • Leeks don’t really need to be harvested, unless you live in a very cold area; otherwise, they can just wait in the ground until you need them
  • when pencil thin, they tend to be sweeter than scallions and make a good winter substitute for them FV
  • Aim for harvesting leeks at less than 1″ in diameter (at least for fermenting) FV
  • harvest when stems are thick and succulent, but before bulbing occurs SoC
  • a deep mulch will allow harvest until hard freeze SoC

Harvest Methods

  • harvest whole plants by gently twisting and lifting; in heavy soils you may need to loosen soil with a fork to avoid damaging the stems SoC

Storage of harvest


leeks prepared for storage

leeks prepared for storage

  • can be stored in a root cellar
  • Freshly harvested leeks can be kept for at least a week wrapped in a damp paper towel and stored in a plastic bag in the refrigerator.



Freezing leeks seems to be the favored method of preserving them.

  1. Wash & slice leeks – white parts only
  2. Blanch for 2-3 minutes, then put them in very icy ice water
  3. Drain well
  4. Spread onto a sheet pan and freeze until hard (about 30 mins)
  5. Pack into freezer bags (vacuum sealers are a bonus)

To cook from frozen, boil for 8 minutes, or add directly to soups or stews. They won’t brown & crisp nicely if they are wet.

Pickled or Fermented

  • Like other members in the onion tribe, under fermentation the harsh pungency of the raw flavor is mellowed FV
  • Leeks blend nicely with sauerkraut, and like onions, are versatile FV
    • try leeks in the crock with cabbage and root vegetables like carrots, horseradish, turnips, etc
    • consider a leek-wine kraut: prepare a leek-cabbage kraut and finish the fermentation with a splash of wine


Drying is a great way to preserve your leeks – and to use up the green tops that are too tough to cook and eat; the dark green leaves, while fibrous and inedible when fresh, turn into a fantastic spice when dried and ground to a powder (Here’s the recipe to dry leek greens or tops)


Nutritional Benefits & Values

  • 10 g of fructan per leek – this is one of the highest vegetables in fructan (fructan is a fiber and prebiotic for good gut bacteria) WWW
  • When used in fermented recipes, they are believed to reduce the speed of fermentation, allowing more time for the flavor to develop beyond just the acidity FV




  • trim & discard the roots
  • slice off the dark green leaves, leaving the tight light green, tender leaves (reserve for drying)
  • slice the stalk in half, lengthwise, and rinse under cold running water to remove the grit between each of the leaf layers
  • slice or chop per recipe; most often they are sliced thinly

Cooking Methods

  • fresh eating
  • sauteing or stir-frying
  • baking
  • grilling
  • braising or in soups


  • Asian recipes tend to use small leeks, about scallion-size FV
  • slicing thinly, then sauteed in butter is the basis of potato-leek soup or vichyssoise
  • can be used as a substitute for garlic or onions, although they are more fibrous, so they need to be sliced more thinly


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.