Sow Leek Seeds In Batches Between February And June – Gardener Shares How
Elizabeth is a Permaculture Garden Designer, Sustainability Consultant and Professional Writer, working as an advocate for positive change. She graduated from the University of St. Andrews with an MA in English and Philosophy and obtained a Diploma in Applied Permaculture Design from the Permaculture Association.
Reviewed By COLIN SKELLY
Colin is a Horticulturist and Horticultural Consultant with experience in a range of practical and managerial roles across heritage, commercial and public horticulture. He holds the Royal Horticultural Society’s Master of Horticulture award and has a particular interest in horticultural ecology and naturalistic planting for habitat and climate resilience.
Leeks are a wonderful vegetable to grow in the UK and, fortunately, they are not too challenging to grow from seed either.
Sow leek seeds in batches between February and June and you can potentially harvest and eat leeks from late-August right through winter – to February the following year.
The process of growing leeks from seed is very easy, as we explain in the guide below.
| Difficulty | Easy |
| Equipment Required | Seeds, seed tray or pot, growing medium |
| When To Sow | February to June |
| When To Plant Out | April to June |
Choosing A Variety
Before you can sow leek seeds you will need to determine which variety you would like to grow.
There are many named cultivars to choose from.
Some cultivars that have received an RHS Award of Garden Merit (AGM) include:
- ‘Autumn Giant Porvite’
- ‘Blauwgroene Winter’
- ‘Cairngorm’
- ‘Jolant’
- ‘Longbow’
- ‘Krypton’
- ‘Mammoth Blanch’
- ‘Oarsman’
- ‘Porbella’
- ‘Stamford’
When choosing a variety, remember that some are suited to harvesting before the frosts set in, others are suited for winter growing, whilst others still mature late and are suited to harvesting in late winter and early spring.
When To Sow Leeks
Leek seeds can be sown indoors from February to June or outside from March to June.
Sowing earlier will provide you with leeks in late summer and early autumn, and later sowing can potentially see you right through the winter months.
It is a great idea to prolong the harvesting period by sowing leek seeds successionally in smaller batches over this period, in order to make sure you can enjoy homegrown leeks over as much of the year as possible.
Where To Grow Leeks
Leeks can be grown in the ground, in raised beds or in large, deep containers, as long as the soil or growing medium is moist but free-draining, fertile and rich in organic matter.
The more rich and fertile the soil or growing medium, the better your leeks will grow.
Plan to grow them in your vegetable garden, in an area with a reasonable amount of sun, and combine them with other vegetables and companion plants for the best results.
Indoor Sowing
When sowing leeks indoors, you should first prepare your seed trays or small pots.
These should be filled with a good quality, peat-free potting compost.
Place the leek seeds on the surface of this growing medium, then cover them over very lightly so that they are covered by a few millimetres of the potting mix.
If growing in small blocks or modules, sow a single seed per block or module.
“I sow my leeks in small modules in February, being careful to label the different cultivars,” shares Master Horticulturist Colin Skelly.
“I use succession sowing and a selection of cultivars to harvest from autumn to late winter, so if I get the labels wrong, I’m in trouble.
“These get thinned and then planted out into the garden as early as I can.”
Once the leek seeds germinate and are large enough to handle, pot up those grown in seed trays into individual small pots.
The young leeks can then be planted out into their final growing position in your garden when they are 15-20cm in height and, ideally, are approaching pencil thickness.
Outdoor Sowing
Alternatively, if you wish to grow a lot of leeks and do not have space to start them indoors, you might consider sowing leeks into a prepared seed bed outdoors that has been well composted or manured and raked to a fine tilth.
It is best not to directly sow leeks into your main growing area, as they will take up a lot of space early in the growing season that can be used for other quick crops.
Sow your seeds thinly in rows, around 15cm apart, around 1 cm deep in the seed bed area.
Then, transplant your young leeks to your vegetable garden in early summer.
Once you have leeks in your growing areas, be sure to tend them well over the summer and autumn months and you should be rewarded with a successful leek harvest later in the year.
