Edibles Grow Sheets

Leek

• Scientific Name

  Allium ampeloprasum var. porrum
• General Information

  

  Leeks are cool season biennials grown as annuals. Easily grown member of the Allium family. They don't form bulbs like their garlic and onion relatives. They develop a six to ten inch edible stem up to three inches in diameter. Will endure, but don't appreciate temperatures consistently above 85 degrees.

• When to Plant

  Start seeds indoors in December and January or outdoors January through March. Plant starts February through April when leeks are about the diameter of a pencil. Leeks may be planted outdoors in the fall, but there is a risk that the plants will go to seed in late winter or early spring before maturity. If the goal is to harvest baby leeks in late fall and early winter, a fall planting is fine. Leeks need a long growing season, about 120 to 150 days from transplant to harvest. Start seeds 10 to 12 weeks before the transplant day. Leek seedlings are relatively easy to separate so transplants can be grown densely in pots.

• Planting

  Choose a location with loose, well-drained soil in full sun where you did not plant members of the onion family the previous year. Since they will be in the ground a long time, a location way from other shorter term annuals is ideal. Tease apart the seedlings and plant each one separately, about four to six inches apart in rows 12 inches apart. For well-blanched stems (most recipes call for only the white and light green parts), make trenches about six inches deep and plant the seedlings about one inch deep. Hill the soil around the base of the plants two to three times as it grows, filling in the trench. You can also plant them conventionally to the base of the first leaf, and then mound up soil around the plants after they have grown a bit. Lightly water the seedlings after planting. Mulch after planting. Alfalfa hay is seedless and a good nitrogen source as well as an effective mulch. You will barely be able to see the shoots through the mulch, but they will grow rapidly. 

   

• Soil Requirements

  Leeks prefer a neutral soil, pH 6.0 to 7.0. They need at least six hours of full sun sheltered from cold winter winds. Leeks are heavy feeders and like a weed-free spot enriched with fully composted organic material. It is important that the soil is moisture-retentive. Work organic matter into your soil at least six to eight inches deep, removing stones, then level and smooth. Control weeds through regular cultivation, being careful to avoid damaging the shallow roots of the leeks. Weed control is particularly important during the first two months of growth.

   

• Water Requirements

  Leeks require regular water. Water stress reduces yields and plant size. Water needs are critical since rooting depth in leeks is shallow and drought stress during growth will decrease yield. Organic mulches help conserve water, supply extra nutrients, and reduce weeding.

   

• Fertilizing

  If you want to provide supplemental fertilizer, use a low-value, balanced, organic vegetable food such as fish emulsion.

   

• Pollination

  Does not need pollinators.

• Harvesting

  Leeks are ready to harvest when they are about one to two inches in diameter, but check the specific variety that you planted, as size at maturity can vary. Harvest as needed in winter, but finish picking before the plant goes to seed. Sever the roots under the stalks and twist the stalks back and forth to loosen them and ease them out of the ground.

   

• Storage

  Leeks are usually stored in the ground and harvested as needed. Leeks will keep in storage for several weeks if maintained at temperatures near 35 degrees F and a relative humidity near 90 percent.

   

• Good Varieties for Marin

  Most varieties work well.

• Helpful Tips

  To prevent disease problems, rotate the location of your Allium family crops so they are not always planted in the same area.

   

• Common Problems

  Leeks are subject to similar pests and diseases as onion and garlic.

• Pests- Diseases & More

  N / A