You could be eating delicious leeks from your garden for six months or more by choosing varieties for continuity of cropping. One of the most useful and versatile of all vegetables, leeks should be planted in an open site in rich, well dug soil with plenty of well-rotted organic matter, which can be incorporated just before the young plants are set out. Their fibrous roots improve the soil's structure, but remember to rotate their growing position, as you would with onions. They produce a natural white shank, but its length of blanch can be increased by earthing up the plants as they develop through the summer and autumn.
How to Sow and Grow Leeks
Sow indoors: 0.5cm(¼in) deep in a tray of compost. Water well and place in a cold frame or unheated greenhouse. After ensuring they are kept moist, transplant 5cm(2in) apart to other trays when large enough to handle. Slowly accustom young plants to outside conditions, avoiding frosts, before planting out.
Sow outdoors: Thinly in a seed bed, sow 1.5cm(½in) deep directly into finely prepared soil which has already been watered. Seedlings usually appear within 14-21 days. Water well until plants are established. Transplant 10cm(4in) apart into 15cm(6in) deep holes. Allow 30cm(12in) between rows.