Leek leek Leek is a hardy biennial commonly grown as an annual for its long, blanched stems and mild onion flavor. There are early (summer) and late (winter) varieties; late types are more cold-hardy and store better in the ground. Blanching length and stem thickness depend on variety and technique (deep planting, dibber holes, gradual earthing-up, or using collars). Leeks tolerate frost; many winter varieties withstand -10 to -15 °C, allowing harvest well into winter in much of Sweden. For the longest white shanks, start early, grow steadily without checks, and maintain even moisture and fertility. Growing conditions LightFull sun (6–8+ hours). Tolerates light shade but yields are lower. Soil typeDeep, fertile, moisture-retentive but well-drained loam rich in organic matter; fine tilth for sowing. Improve with compost and a little well-rotted manure before planting. Water requirementConsistent moisture; ~25–30 mm per week. Avoid waterlogging. Mulch to stabilize moisture. Nutrient requirementHigh nitrogen and moderate potassium. Avoid fresh, high-ammonia manure at planting; use well-rotted compost and side-dressings. Back to plant list
