You need a little patience with leeks as they have a long growing period to reach full maturity, but they are very winter hardy, and can be picked during the winter months and holiday dinners.  

Soil

Leeks will benefit from well-drained soil that has been mannered the previous winter with the addition of plenty of organic matter too. The application of a well balance fertilizer such as vegetable garden 4-4-4 at the rate of 5-7 lbs per 100 square foot.  

Sowing

In the spring sow seeds thinly in a prepared seedbed no more than 1/2” inch deep or in seed trays. 

Growing 

Young plants like to be transplanted in April-June when they are about as tall and thick as a pencil. Use a dibbler to make holes 4-6 inches apart. Drop the leeks down into their holes and then water in. There’s no need to fill the holes with soil as the action of watering in will provide sufficient cover for the roots and base of the plant. Keep competing weeds out as they rob the plants of nutrients. Keep plants watered thoroughly in dry weather. In the autumn, earth up soil around the base a little as this will result in greater blanching of the stem. 

Harvesting

The great thing about leeks is that you can just leave them in the ground until you are ready to lift them. You can also pick baby leeks as well before then for use in salads and stews.

Leeks are great for making soufflés, soups and sautéing as a replacement for any onion.