The Best Time for Harvesting Leeks

Leeks are part of the onion family, but they don’t form a bulb like an onion. Instead, they grow with a long, edible stem or shank. These vegetables are nutritious, providing folate, vitamin C and A, as well as cancer-fighting kaempferol. Knowing when to pick leeks is important for getting the best flavor and retaining the nutrients.


When to Harvest Leeks

Most leek varieties mature in about six months, but you can begin harvesting them when they reach one inch in diameter. The white part of the stem should be about 3-inches long. The top part of the stems, known as the flag, should be a deep, blue-green color. The stems do not dry out as they mature like onion stems and shallots do.

Depending on your weather conditions, you can harvest leeks starting late in the summer, until spring. In mild climates, leeks are strong enough to winter over for a spring harvest. If you overwinter your leeks, mound up the soil and mulch around the base for extra protection.

Extend Harvest with Different Leek Varieties

When choosing which leek varieties to plant in your garden, think about planting ones that have different maturation rates, so you can extend your harvest time. The following are a various leek varieties and their maturation times:

  • King Richard – This is an early maturing leek variety, which reaches maturation in 75 days when grown from seed. It doesn’t winter over, but resists medium to heavy frosts and temperatures of 32°F (0°C).
  • Tadorna Blue – This leek variety can overwinter in areas where the temperature get as low as 20°F (-6°C). Leeks reach maturity in about 100 days.
  • Bandit– This variety matures in 120 days, extending your leek harvest throughout the winter. This is a very winter-tolerant variety.

How to Harvest Leeks

When harvesting any bulbs from the onion family, including leeks, shallots, garlic and onions, use a garden fork to loosen the soil around the roots. Keep a safe distance away from the bulbs to prevent piercing them with the tines.

Once you dig them out of the soil, grasp the shaft, and shake off any loose dirt. Trim off the roots, and rinse your leeks in cold water until all the grit is gone. You can store them in the refrigerator for about two weeks. They decay quickly, if left at room temperature.