Growing your own Leeks

Growing Leeks

There is nothing common about Allium porrum or the common garden leek. The king of the onion family, it will impart the finest of flavours to any dish, be it soup, stew or a stand-alone leek dish. It is easy to grow, even in the coldest of winters, will add structural beauty to your veggie garden. The purple pincushion flowers (if you spoil yourself by letting it bloom) are just too gorgeous and edible to boot!

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Starting off

Leeks can be grown from seed or ready-to-plant seedlings, available at Lifestyle Home Garden. Seeds can be sown from early autumn to late winter. Staggered planting of different varieties will ensure a continuous crop throughout the growing season.

It is best to sow the seeds in cavity trays filled with a reputable commercial germination soil or a germination mix of your own choice. Keep the seedlings moist and under shade cloth or in a greenhouse to protect them from harsh sun and cold winds. Leeks are slow growers, so you will have to be patient, but the rewards are worth waiting for! From sowing to harvesting can take up to 6 months, but plants bought as seedlings will be ready for harvesting in about four months.

Thin seedlings out when they are strong enough to be handled and plant individually into trays with larger cavities or small pots. Once the seedlings are about 15cm tall and/or have reached pencil thickness (±8 weeks), they are ready to be transplanted into beds. Harden off the seedlings by placing them outside in the sun for more extended periods every day for about a week before transplanting. Ready, hardened off seedlings are often grown and sold in a ‘bunch’ and will need to be carefully separated when you plant them.

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Off to bed

Prepare the bed or beds for your leeks in a sheltered, full sun position, i.e. at least 6 hours of sun per day. Remove all weeds, large stones and clots and prepare the soil by digging it over deeply and adding a generous layer of compost together with one handful of organic 2:3:2 fertiliser per square meter. The soil should be of a fine texture, well-draining and preferably neutral. Rake the soil to level it.

Use a dibber, dowel or the handle of your garden trowel to make rows of planting holes about 10cm apart and 30cm between rows. Make the holes as deep as the length of the seedlings’ stems – at least two thirds of the seedling should be below soil level to ensure sturdy plants with white shanks. Carefully place the seedlings in the holes and fill the holes with water, allowing the surrounding soil to gently fill the holes, without firming the soil down.


  • It is important to keep your leeks moist, but never waterlogged. Watering should preferably be done early in the morning.
  • When seedlings are big enough, spread a layer of fine mulch around the plants, steering clear of the base of the plants.
  • Feed every 2-3 weeks with a liquid seaweed-based fertiliser.
  • About 2 months after planting, feed with a granular, organic fertiliser, like 6:3:4, at the recommended rate.
  • Carefully remove any weeds around the plants by hand to avoid damage to the roots.
  • Unless you have selected a self-blanching leek variety, regularly mound the surrounding soil up against the stems to ensure a beautifully blanched and tender stem.

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Picking for the pot

Leeks don’t produce bulbs like onions, but rather a long, cylindrical stem, topped with folded leaf sheaths. These are parts that are most often used for cooking.  Start harvesting your leeks when the stems are roughly 1cm thick, for baby leeks, and about 2cm thick and 15cm long for mature leeks (about 13 weeks after transplanting them). Stagger the picking and only pick what you need to use on the day, if possible. Carefully loosen the soil around the roots of the leeks with a long trowel or fork and pull up by hand. Remove the roots and wash thoroughly to remove all grit between the layers. Store in a cold place.

Harvest your leeks before it gets too hot or they will go to flower. If you have a lot of plants, however, you could allow some to flower so that seeds can be harvested for next season’s crop. Just be aware that once leeks have bolted, they are not as pleasant on the palate.

We all need a good mate

Great companions for leeks are members of the cabbage family, carrots, celeriac, caraway and celery. A great space-saving idea is to plant fast-growing radishes and loose-leaf lettuce plants in the gaps between the slower growing leeks.

Rather avoid combining leeks with peas – one of them won’t be happy.

Leek History 101

Leeks originate from the Middle East and Eastern Mediterranean. They were grown and loved as a staple food by Egyptians more than 4000 ago.  The Emperor Nero ate them on a daily basis, believing that they strengthened his voice and Hippocrates prescribed them as a cure for nosebleeds. Spread across Europe and the British Isles by the Romans, it is now, strangely enough, the national symbol of Wales and is proudly worn on St. David’s Day to honour the Welsh patron saint.

FYI: The only places where leeks are not welcome – in fact they are banned – are ships…

…just pulling your leeks!

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