If you’re looking for an easy-to-grow vegetable that will add a touch of elegance to your garden, look no further than leeks! Leeks are a member of the onion family and are related to both onions and garlic. They can be grown either in the ground or in containers, and they are tolerant of both cold weather and drought.

Unlike onions, leeks develop long, succulent stems rather than producing large bulbs. These stems are used as an onion substitute in many dishes. Leeks are cooler than onions. They perform the same jobs (use them anywhere you would a regular cooking onion) they’re sweeter, with a more delicate flavour – their own special ‘leeky’ flavour.

How to Grow Leeks

Grow in seed trays until about 20cm (8in) tall. They look rather like large blades of grass at that stage. Plant you leeks in full sun in fertile, well-drained soil. You can plant you seedling into into trenches or individual deep holes with black soil from the compost heap – make the holes using a dibber.

When transplanting leeks, cut back the leaves, as this helps the stem to develop. Another method is to set the base of the stem about 6 inches under ground, not filling in at first, but allowing rain and subsequent cultivation to level the ground, and then, when the plants are growing vigorously, they are earthed up.

This is a better method than growing them in trenches, as the roots do not get into dead soil. When the plants are small, the space between the rows should be used for growing lettuces and radishes as catch crops. Leeks need regular watering and an application of seaweed tonic every two to three weeks to provide them with iron and selenium and promote quick growth and plump, tender stems.

Best soil conditions for growing leeks

Leeks don’t grow very well in a strongly acid soil preferring instead neutral to slightly alkaline soils (6.0 – 8.0 approx). If the pH (relative acidity or alkalinity) of your soil is not suited to the vegetable, then soil nutrients such as Nitrogen, Phosphorus, Potassium, Iron, Boron, Copper, Manganese and Zinc start to become unavailable, leading to poor crops. You can use a home soil test to determine your soils ph. By taking account of the test results you can then decide how much if any amendments are required to sort out the to pH of your vegetable garden soil.

Remember that the Leek is a gross feeder, and can absorb large quantities of plant food. When the plants are growing, an occasional application of liquid manure or Nitrate of Soda will help to keep them moving. Leeks also require an abundance of moisture, and must be kept well watered while the crop is growing. 

When they are tall enough, earth them up to bleach the stems. Pull your leeks as and when you need them. Grasp the stem and carefully lever out the root from beneath with a hand fork, then shake off the soil. Leek plants take about 6 months to come to maturity.

Leek Growing Tips

• Should Green Leeks be required, do no earthing up
• Avoid planting leeks in soil that waterlogs or dries out rapidly
• As you grow leeks for their leaves, ensure a rich soil with lots of organic matter
• Grow giant leeks using wide and long PVC pipe
• Take care when weeding because the roots and stems are easily damaged
• Conserve moisture in a dry summer by spreading a one to two inch thick layer of grass clippings on the soil around the leeks

The best sorts of leeks for the Home Gardener are The Lyon, American Flag, London Flag, and Monstrous Carentan.

companion planting for leeks

Companion planting for leeks is a great way to improve the health and yield of your crop. When companion planting, it’s important to select companion plants that are beneficial to each other – either in terms of nutrient exchange, insect control or pest repellence. Some companion plants that work well with leeks include carrots, celery, beets and parsley. These companion plants can help protect leeks from disease and support the growth of stronger roots. Carrots in particular provide an additional benefit; when grown alongside leeks they will reduce their pungency. Other good companion plants for growing leeks include chamomile, garlic and nasturtiums. The combination creates a soil-enhancing ‘mini-ecosystem’ that helps to naturally protect each plant from potential pests. Companion planting with companion flowers like alyssum can also help attract beneficial insects such as hoverflies which prey on garden pests.