Leek

1. 1

   Sow seed

   March to April. Indoors in modules at 12–15°C, or direct into a seedbed once soil is workable. Sow thinly. Germination in 2–3 weeks.

2. 2

   Prepare the bed

   Full sun, deep fertile soil, fork in well-rotted compost. Leeks need a long growing season and plenty of feeding.

3. 3

   Transplant when pencil-thick

   June to July. Seedlings should be 15–20 cm tall and pencil-thick. Trim the leaf tips back by a third (reduces water loss while roots re-establish).

4. 4

   Drop into dibbed holes

   Use a thick dibber or rake handle to make 15 cm-deep holes, 15 cm apart in rows 30 cm apart. Drop one seedling into each hole. Water in but don't fill the hole with soil — the air gap is what blanches the lower stem white.

5. 5

   Net against allium leaf miner

   From March until the crop is lifted. Phytomyza gymnostoma is a relatively new pest (first UK sighting 2002, now widespread) — the larvae tunnel into stems leaving them slimy and unusable. Enviromesh or fine netting stops the adult fly laying.

6. 6

   Earth up later for more blanching

   Optional, for show-quality long white shanks. Draw soil up around the stems through autumn. Most allotment growers skip this; the dibbed holes give enough blanching for everyday eating.

7. 7

   Lift through winter

   From October onwards, lift as needed with a fork (don't pull — the roots snap off). Frost actually improves the flavour. The crop sits happily in the ground until April.

Allium leaf miner and leek moth are increasing threats; rust also common.