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Leek

Allium ampeloprasum

Vegetable

Leeks are hardy alliums with a mild, sweet onion flavour that can be harvested through winter in many climates. They are excellent companion plants whose strong scent deters carrot fly and other pests.

Growing Conditions

Sunlight

Full Sun

Water Needs

Moderate

Soil

Rich, well-draining loam; pH 6.0–7.0

Spacing

6 inches

Days to Maturity

100–130 days from transplant

Growing Zones

1
2
3
4
5
6
7
8
9
10
11
12
13

Thrives in USDA Zones 3–10

Companion Planting

Good Companions

Keep Away From

When to Plant

  • Start Indoors

    10–12 weeks before last frost

  • Transplant

    4–6 weeks before last frost; plant deep to blanch stems

  • Harvest

    100–130 days; can leave in ground through winter in mild climates

Organic Growing Tips

  • Plant in trenches and earth up progressively to blanch the white stem portion as plants grow.

  • Interplant with carrots — each repels the other's primary fly pest through aromatic masking.

  • Apply neem oil spray at first signs of rust to slow its progression through the crop.

  • Harvest as needed through winter; leeks improve in flavour after exposure to frost.

Common Pests

  • Leek Rust
  • Onion Fly
  • Thrips
  • Allium Leaf Miner

All pest management in Garden uses safe, organic, non-toxic methods only. No synthetic pesticides, ever.