Leeks, with their mild onion flavor, are a staple of many cuisines. They are wonderful added to soups and stews, and I can't imagine my Thanksgiving stuffing without them. As an added bonus, they're very easy to grow. Here's what you need to know to grow your own leeks.
Where to Grow Leeks
Leeks grow well in just about every climate zone, though gardeners in zone three and lower may have trouble getting leeks of decent size during their short season. They require rich, well-drained soil. It is best to amend your soil with plenty of compost and/or composted manure before planting. Leeks grow best in full sun, but will also tolerate some shade.
Leeks are best grown in traditional garden beds or raised beds. They can be grown in containers, but be sure to have a deep enough container so that you can add soil to blanch the stalks as they grow.
You can often find transplants for leeks in nurseries and garden centers, but these are rarely organically grown. However, it is very easy to start your own leeks from seeds indoors.
Sow seeds indoors, 12 weeks before your last spring frost date. This will ensure that you have decent-sized leeks to plant in your garden, since they take a while to get going. You can sow the seeds in flats, but it's best to transplant the leeks into individual pots or cell packs once they're large enough to handle; this will help them grow larger so they'll be easier to transplant outdoors.
After your last frost date, harden off your seedlings and plant them in the garden. Leeks should be planted six inches apart, and six inches deep. You can do this by making a trench six inches deep and setting the leeks into it, or by using a dibble or small trowel to make individual holes, and dropping the seedlings into them. Backfill, burying all but the top inch or so of the leaves. Water them well.
How to Grow Organic Leeks
Leeks require very little care once they're established. Simply make sure they get steady moisture (as dry soil will cause your leeks to be tough and kind of stringy) and foliar feed monthly with fish emulsion or compost tea.
Other than watering, you'll want to keep hilling soil around the leeks to blanch the stem as it grows taller. You can also simply pull mulch up against the stems as they grow. The more you blanch, the more tender white stalk you'll have.
Leek Pests and Problems
Leeks, as most other members of the onion family, have very few pest and disease problems. Root maggot can sometimes be a problem; simply make sure that you're not growing your leeks in an area that grew any other onion family members (onions, shallots, or green onions) within the last year.
You can harvest leeks as soon as they're large enough to use, about an inch in diameter. This usually takes anywhere from 70 to 100 days, depending on the variety you've planted. Simply pull the entire leek from the ground, roots and all. Remove the dark green parts, as these are tough, and use the white part for cooking. Be sure to rinse leeks well; soil can often get caught between the layers inside the leeks.
You can keep harvesting leeks well into the fall, even after a freeze. Mulch them with several inches of straw or autumn leaves, and the soil will stay unfrozen for quite a while. Leeks that overwinter will produce a large (gorgeous!) flower the second year. They'll still be edible, but less tender than leeks harvested in their first year.
Recommended Leek Varieties
- 'King Richard' is one of the earliest leek varieties, maturing in about 75 days.
- Lancelot' is a longer-season leek, about 95 days to harvest, with good cold tolerance.
- 'American Flag' produces very large, flavorful leeks in about 95 days.