Soil :Requires rich, loamy soil that holds moisture well.
Position : Sun or partial shade
Frost tolerant : Yes
Helps: fruit trees, tomatoes, capsicum, peppers, potatoes, brassicas, carrots
Helped by: carrots,tomatoes,carrots and African spider plants (Cleome gynandra) together, marigolds (Tagetes ssp),mints
Avoid: peas, beans
Repels: rabbits, slugs, aphids, carrot-fly, cabbage loopers, cabbage maggots, cabbage worms, Japanese beetles
Sow and Plant :Sow indoors in early spring, and move to a protected cold frame if you have one. Transplant when seedlings are about the size of a pencil.
When leeks are almost the size you prefer, blanch them for 2 to 3 weeks by putting a mound of soil, mulch, or a cardboard tube around the base of each stem. Grows best in climates where nights remain cool through summer. In mild winter climates, try leeks as a fall-to-spring crop.
Germination: 7-14 days
Spacing : Single Plants: 7″ (20cm) each way; Rows: 5″ (15cm) with 11″ (30cm) row gap
Feeding : In late summer while the weather is still warm, drench plants thoroughly with a water-soluble plant food.
Harvesting :Dig as needed in the kitchen. In cold winter climates, dig plants before the ground freezes in early winter.
Time to harvest: Leeks require 170 days from sowing and 80 days from transplanting to reach harvest. Leeks are ready for harvest when stems reach 1 to 2 inches in diameter and leaves are 6 to 8 inches tall. About midsummer, cut off the top half of leaves to encourage full stalk growth. Lift leeks as you need them but complete the harvest before the first freeze.
Troubleshooting :Struggling plants may be infested with onion root maggots, which are easy to see when you dig up a plant. Promptly remove affected plants.
Onion thrips may attack leeks in dry weather. Hose thrips off of plants.