Growing Leeks

allium porrum : Amaryllidaceae / the onion family

Jan F M A M J J A S O N Dec
  S S                  
      T T              
      P P P            

(Best months for growing Leeks in USA - Zone 5a regions)

  • S = Plant undercover in seed trays
  • T = Plant out (transplant) seedlings
  • P = Sow seed
  • Easy to grow. Grow in seed trays, and plant out in 4-6 weeks. Sow seed at a depth approximately three times the diameter of the seed. Best planted at soil temperatures between 46°F and 86°F. (Show °C/cm)
  • Space plants: 4 - 8 inches apart
  • Harvest in 15-18 weeks. Loosen with a fork rather than pull by hand..
  • Compatible with (can grow beside): Carrots
  • Almost ready to use
  • Leek

A member of the onion family. Looks rather like a large spring onion (scallion). Grow in seed trays or punnets until about 20 cm (8 in) tall. They look rather like large blades of grass at that stage. Then plant out into trenches or individual deep holes. The aim is to blanch the stems while the plants are growing. Trenches should be about 20 - 25 cm (8 - 10 in) deep. Set the seedlings 10 - 15 cm (4 - 6 in) apart then add enough soil to just cover the roots. As the plants grow fill the trench. Otherwise - make holes with a dibble or suitable stick 15 cm (6 in) deep and 3 - 4 cm (1.5 - 2 in) wide. Drop a seedling in each and water enough to cover the roots with soil. As they grow, watering will gradually fill the hole.

Leeks prefer moist clay soils. Keep soil moist and loose, mulch will help.

Culinary hints - cooking and eating Leeks

Trim off the roots and any damaged leaves.
Young ones can be used whole with some of the green leaves.
Wash thoroughly as the earth tends to get inside.
Chop and fry in butter (or olive oil) until tender.
Can be added to casserole meals, allowing time to cook through.
Leek and mushroom make a tasty combination for a tart filling.

Your comments and tips

29 May 23, Dave (Australia - sub-tropical climate)
I have stopped trying to grow ordinary leeks and now grow perpetual ones. They absolutely thrive in our subtropical garden and continually keep making side shoots so I never have to plant seeds. I thoroughly recommend them for people if they want to set and forget
19 Aug 22, NewbieGardna (Australia - sub-tropical climate)
I planted teeny li'l leek seedlings a few weeks ago. They are now starting to look like li'l leeks. Hope they keep growing.
19 Mar 22, Dionne (Australia - sub-tropical climate)
We grown American Flag with great success. We mostly direct seed and sometimes transplant. We always broadfork a bed before planting and add a little ag lime (especially pre-seeding with alliums). We don't let them get gigantic like you see in the shop. You can, but that requires transplanting into a small trench and then hilling up to blanche. We find the bunches of baby leeks just as popular as the large ones. Leeks with asparagus are so wonderful on pizza with a good French sorrel and parsley pesto base! Leeks can handle more water than you realise.
06 Dec 20, Terry Shannon (Australia - temperate climate)
My Welsh Wonder leeks are always skinny looking things..an occasional .two-finger thickness is the best we ever get. I fertilize them and they get plenty of water and are in sandy neutral soil We look at the produce in the stores and despair :-( I shall appreciate any suggestions Cheerio.. terry
07 Dec 20, Anonymous (Australia - temperate climate)
I would suggest an autumn planting. Maybe build your soil up with compost and manures 2-3 mths before planting. Make sure it is all rotted into the soil by plant time. Hard to beat the commercial people, they are spot on with fertiliser requirements and watering. We kind of half guess it.
10 Mar 20, Mike (New Zealand - cool/mountain climate)
Have just transplanted very small leak plants four centimetres in to garden on the first of March. Does anyone know if they will mature?
11 Mar 20, Another gardener (Australia - sub-tropical climate)
Read the notes here. Transplant out at 4-6 weeks. Sounds like you are pretty close to that. Protect them the first week or two from the sun and wind while they establish themselves. A light watering each day also.
04 Mar 20, Jenny (Australia - sub-tropical climate)
I planted a leek from a seedling in Brisbane in February. It was doing really well until this morning when it went from fine to limp and lying on the ground within the space of about half an hour. Any idea what went wrong? When i peeled the leaves back the inside was literally mush. I thought I might’ve over watered but when I dug the plant out the soil was quite dry
04 Mar 20, Anon (Australia - sub-tropical climate)
Maybe water was caught down between the leaves and it just went rotten.
20 Feb 19, Helena (Australia - sub-tropical climate)
What type/variety of leek is best suited for Sydney South West area?
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