When to plant Leeks in the UK

Around mid-March to early April, dig the bed well and work in compost. Leeks do best in moisture-retentive but free-draining soil, and a loose, stone-free tilth helps the stems grow straight.

Sow seeds thinly in modules or a seed tray around mid-February to mid-March, about 1 cm deep. Keep them at 15–18 °C and water gently so the compost stays moist but not sodden.

Move seedlings on when they are large enough to handle, from early March. Pot them into small modules or deeper trays so the roots can develop without crowding.

Set plants outside for a few hours a day before planting out. Do this over mid-April to early May so they adjust to wind, sun and cooler nights without checking growth.

Plant sturdy seedlings into deep dibbed holes around mid-April to early June, leaving just the base of the leaves at soil level. Water in thoroughly at once, then let the soil settle naturally around the roots rather than firming hard.

Keep the rows weed-free and draw soil up around the stems as they thicken. Start from mid-April and repeat as the plants grow, keeping moisture steady in dry spells so the stems stay tender and pale.

Lift leeks from late September once the stems are a usable size, then keep picking through mid-February. Loosen the soil with a fork before pulling and take only the stems needed.