How to Grow Leeks

mediumGardeningseasonal10 steps

Safety Warnings

Avoid planting where other onion family crops have been grown in the past 3 years to prevent disease.

Garden fork — For lifting roots without breaking stems

Floating row covers — To prevent onion maggot infestations

Cell-type containers — For transplanting indoor seedlings

Compost or manure — Organic matter, ideally chicken manure(As needed for soil prep)

Worm castings — Nutrient-rich soil amendment(As needed)

Paper collars — Paper or cardboard towel centers(1 per plant)

Mulch — Organic material for moisture retention(As needed)

Prepare deep, well-drained soil rich in organic matter by digging in compost or manure two weeks before planting.

Tip: Raised beds are ideal for leeks.

Sow seeds either by direct seeding 4 weeks before last frost (1/2 inch deep) or starting transplants indoors 8-10 weeks before last frost.

Tip: Long-season varieties are best started indoors.

Transplant seedlings 6-12 inches tall into full sun, planting them deeply so only a few inches of leaf show above the soil.

Tip: Deep planting reduces the need for extensive hilling later.

Water young plants frequently and maintain consistent moisture due to their shallow root systems.

Tip: Water weekly during dry weather and use mulch to suppress weeds.

Apply fertilizer every few weeks; aged chicken manure and worm castings are excellent sources of nutrients.

Tip: Maturity is heavily affected by available nutrients and water.

Blanch the stems to increase the edible white portion and sweeten the taste by hilling soil around the stems several times as they grow.

Tip: Avoid one single large hilling when plants are young to prevent rot.

Alternatively, tie a paper collar around the stem and gently hill earth around it, adding more collars as the plant grows.

Tip: Be careful not to get soil between the collar and the stem to avoid rot.

Monitor for pests such as onion maggot and thrips, and diseases like purple blotch or Botrytis leaf blight.

Tip: Check paper collars for hiding slugs and snails.

Harvest when stems reach approximately 2.5cm in diameter.

Tip: For autumn plantings, ensure they are to fatten up before winter.

Dig carefully around the leek and lift with a garden fork.

Tip: Do not pull the leek, as the stem is likely to break.

The white part of the leek is the primary edible portion, but the green leaves can be used to make stock.
Newer cultivars may mature faster (3-4 months) compared to traditional varieties (6 months).

Synthesized from 2 verified sources:

GrowstuffView →

Cornell ExtensionView →