Growing Leeks:
How to Grow Leeks Organically

Growing leeks is a breeze in healthy, well-drained soil and full sun. As long as they’re well-mulched, they’ll also survive in the ground throughout winter, providing for a welcomed late harvest.

Growing Leeks: Plant Snapshot (Allium porrum)

Growing Leeks
  • Family: Liliaceae (Onion family)
  • Annual or Perennial? Perennial – Ready to harvest in 30 to 45 weeks after planting
  • Recommended varieties: Lancelot, American Flag, Lincoln, Gigante d'Inverno
  • Cold tolerance: Hardy – Will survive hard frosts and can be planted 2 to 3 weeks before the average date of the last 32 degree F (0 degree C) temperature in spring.
  • Required Sun: Full sun (at least 6 hours each day)
  • When planning vegetable crop rotation, group with crops from this family: Alliaceae: garlic, shallot
  • Companion plants (see Companion Planting Charts for more info):
    • Companions: Bush bean, beet, carrot, celery, garlic, onion, parsley, tomato
    • Avoid: Legumes
Back to top of Growing Leeks - How to Grow Leeks Organically

Growing Leeks: Planting the Seed

Where to Find Planting Supplies...

The following resources offer effective, healthy and/or well-rounded options. Click the links to go there now...

If you live in a cold climate, you can plant leeks in containers or seed flats about 8 weeks before your last frost. If you live in a warmer climate you can start leeks indoors about three weeks before your last frost date.

And if you’re not up for seed starting indoors, purchase a started plant or plant the seed directly into the soil when the soil temperature reaches 75 degrees F (24 C).

If you direct seed, plant your leeks in beds closely together but with enough room so that their leaves can branch out – 6 inches (15 cm) apart should be plenty.

During your leek plants’ early stages, keep the soil well-watered and apply a liquid organic garden fertilizer every couple of weeks.

Snapshot: Planting Leeks

  • Planting depth: about ¼ inch (6.4 mm)
  • Spacing in rows: about 6 inches (15.24 cm)
  • Germination soil temperature: 70 to 75 degrees F (21.1 to 23.9 degrees C)
  • Days to germination: 7 to 14 days
Back to top of How to Grow Leeks Organically

Growing Leeks: From Germination to Pre-Harvest

Where to Find Growing & Plant Care Supplies...

For effectice, healthy and/or well-rounded options, click the following links...

Before transplanting your leeks (either from a started plant that you bought or from one you started indoors), wait until temperatures stay above 40 degrees F (4.44 degrees C) outside. Harden seedlings off by reducing the water and temperature for about 7 days before planting them in your garden.

Leeks’ shallow roots require frequent watering. Give them enough to keep their stems moist and add a healthy layer of organic mulch to prevent weed competition and soil moisture loss.

Snapshot: Growing Leeks

  • Preferred soil pH (see soil pH tester for more information): 6.0 to 7.5
  • Growing soil temperature: 60 to 75 degrees F (16 to 23.9 degrees C)
Back to top of How to Grow Leeks Organically

Growing Leeks: Harvesting Time

When you harvest your leeks depends on the variety you grow. Some can be harvested about 10 weeks after planting in the late summer while others should wait until late fall.

When they're ready, dig up as much as you need and leave the rest in the ground until you’re ready for more. If you plan to wait until after the frosts begin, protect your leeks from the cold with a thick layer of mulch.

Snapshot: Harvesting Leeks

  • Time to harvest: About 10 to 15 weeks
Back to top of How to Grow Leeks Organically

Storing Leeks and Freezing Leeks

If your plant is to store them for use throughout the winter, why not just leave them in the ground? As long as you apply a thick layer of mulch (or plastic mulch) before the first hard frost, you can dig them up as needed.

For short-term storage, put them in a plastic sealable bag prior to washing or trimming and slide them into your refrigerator’s vegetable drawer. They’ll last for a couple of weeks if stored in this fashion.

Leeks don’t freeze well, so for longer storage pack them in a wooden box interspersed with moist soil from their garden bed and store in a cool, dry place.

Leek seeds have longevity of about 2 years.

Snapshot: Storing Leeks & Freezing Leeks

  • Storage temperature: 50 degrees F (10 degrees C)
  • Humidity: 95 to 100% relative humidity (if refrigerated; soil will provide moisture if soil-packed for longer-term storage)
  • Storage life (refrigerated): about 14 days
  • Storage life (frozen): Leeks do not freeze well; see section above for long-term storage recommendation
  • Seed longevity: 2 years
Back to top of How to Grow Leeks Organically

Growing Leeks: Pests & Diseases

The following pests and diseases have been known to affect the success of growing Leeks. For more information about preventing and controlling them, see Organic Garden Pest Control.


  • Cutworms
  • Grasshoppers
  • Leafminers
  • Mites
  • Bulb mites
  • Wheat curl mite
  • Nematodes
  • Onion maggot
  • Snails/slugs
  • Thrips


  • Bacterial soft rots
  • Basal rot
  • Black mold
  • Blue mold rot
  • Botrytis leafspot (Leaf blight)
  • Downy mildew
  • Neck rot (Botrytis bulb rot)
  • Pink root
  • Purple blotch
  • White rot
Back to top of Growing Leeks - How to Grow Leeks Organically

YOUR Experience & Advice About Growing Leeks

growing vegetables Yep - He grew these himself!
Click here to share your photo
or experience

Figured out a unique and effective way to grow them in your region?

Solved a problem that's been plaguing you?

Want to show off a picture of your perfect harvest?

Click here to share your advice, experiences and/or photos.

Back to top of Growing Leeks - How to Grow Leeks Organically

Was this page helpful?  If so, please tell your friends about it with a Facebook like or via Twitter, Pinterest, email or good old fashioned word of mouth. Thank you for supporting our efforts!

New! Comments

Have your say about what you just read! Leave a comment in the box below.

Also see...

Leeks photo is licensed under the Creative Commons Attribution-ShareAlike 2.0 Generic license.

What Visitors Are Saying...

Share your thoughts!
[?] Subscribe To This Site

follow us in feedly
Add to My Yahoo!
Add to My MSN
Subscribe with Bloglines