How to Plant Leeks in the UK: A Complete Growing Guide for Beginners

Introduction

Leeks are one of the UK’s most reliable and rewarding vegetables to grow — hardy, low-maintenance, and packed with flavour. Whether you’re cultivating a full allotment or a small raised bed, learning how to plant leeks in the UK will ensure a steady supply of this versatile veg from autumn through to early spring.

With their long growing season, tolerance of cold, and usefulness in the kitchen, leeks are a staple in any productive garden. In this guide, we’ll walk you through everything you need to know — from sowing to harvesting — including when to plant leeks in the UK climate, how to transplant them, and how to get long, thick, tender stems.

Quick Overview: Planting Leeks in the UK

Why Grow Leeks?

✅ Hardy and frost-tolerant
✅ Low maintenance once established
✅ Can be left in the ground over winter
✅ Takes up little space
✅ Stores well in the ground or lifted

Leeks are ideal for the British climate, performing well in most soils and producing a reliable harvest when many other veg have long since finished.

Choosing the Right Leek Variety (UK)

Choose multiple varieties to extend your harvest through the year.

How to Plant Leeks: Step-by-Step (UK Climate)

🪴 Step 1: Sow Seeds Indoors (January–March)

• Fill seed trays or pots with multi-purpose compost
• Sow seeds 1 cm deep, spacing them thinly
• Keep in a warm spot (15–20°C) or in a propagator
• Germination takes 10–14 days
• Grow until leeks are pencil-thickness (8–10 weeks)

Leek seedlings are thin and grass-like — don’t worry if they look small.

🌱 Step 2: Harden Off and Prepare for Transplanting

Around April to June, when seedlings are 15–20cm tall:

• Harden off gradually by placing trays outside during the day
• Prepare your planting bed by removing weeds and adding well-rotted manure or compost
• Choose a sunny spot with free-draining soil

Avoid freshly manured ground (manure should be at least 6 months old).

🌿 Step 3: Plant Leek Seedlings (The Dibbing Method)

Leeks are best transplanted using the traditional UK dibber method, which helps produce long, blanched stems.

🌾 How to Transplant:

1. Use a dibber or stick to make holes 15–20cm deep
2. Space holes 15cm apart in rows 30cm apart
3. Drop one leek seedling into each hole
4. Do not fill in the hole with soil — simply water it in. The soil will gradually fall in

This method ensures tall, white stems, rather than green stems exposed to sunlight.

💧 Step 4: Watering and Feeding

• Water regularly in dry weather, especially just after transplanting
• Mulch around plants to retain moisture and suppress weeds
• Feed every few weeks with comfrey tea or seaweed feed for better growth

Once established, leeks are fairly drought-tolerant but will grow better with consistent moisture.

✂️ Step 5: General Maintenance

Leeks have few pests and diseases, making them an easy crop for beginners.

When to Harvest Leeks in the UK

Leeks are slow growers, but worth the wait.

• Harvest when stems are around 2–3cm thick
• Use a fork to lift gently — don’t just pull by hand
• Cut roots and remove outer leaves before storage

Leave some in the ground and harvest as needed — leeks are hardy and store well in the soil.

Can You Plant Leeks Directly Outside?

Yes — if sowing in April–May.

• Sow in shallow drills 1cm deep
• Space thinly, and thin seedlings as they grow
• Once they’re 15–20cm tall, transplant using the dibbing method

However, indoor sowing gives you an earlier start and stronger plants.

Growing Leeks in Containers or Small Gardens

Leeks grow well in deep pots, raised beds, or grow bags.

• Use containers at least 30cm deep
• Space 10–15cm apart
• Feed fortnightly and water regularly
• Ideal for patios or balcony veg patches

Great for urban gardeners or limited space.

Common Problems When Growing Leeks (UK)

Leeks are generally trouble-free — just keep an eye on weather-related issues.

Can You Grow Leeks Year After Year?

Yes — by growing perennial varieties like Babington leek or allowing some to go to seed for propagation. However, most cultivated leeks are biennial, so sow fresh seed annually for best results.

Companion Planting with Leeks

Leeks get along well with:

• Carrots – helps deter carrot fly
• Celery and onions – good bedfellows for alliums
• Beetroot – compatible spacing
• Strawberries – helps confuse pests

Avoid planting near beans or peas, which can compete for nutrients.

Conclusion

Growing leeks in the UK is straightforward and rewarding — they’re hardy, dependable, and a brilliant winter crop that provides flavour and nutrition when little else is available.

From sowing seeds in spring to harvesting in the depths of winter, leeks take care of themselves and ask very little in return. With the right technique — particularly dibbing for transplanting — you’ll enjoy tall, tender stems perfect for soups, stews, pies, and roasting.

Add them to your planting plan this year and enjoy a true staple of the British veg garden.

Top 10 Questions and Answers About Planting Leeks in the UK

1. When should I plant leek seeds in the UK?

Sow indoors from January to March; transplant from April to June.

2. What’s the best soil for leeks?

Free-draining, fertile soil enriched with compost or well-rotted manure.

3. How do I get long, white stems on my leeks?

Use the dibbing method and water into deep holes — don’t fill with soil.

4. Can I grow leeks in containers?

Yes — use a pot at least 30cm deep and space leeks 10–15cm apart.

5. Do leeks need full sun?

Preferably yes, but they’ll tolerate partial shade.

6. Can I plant supermarket leeks?

No — use certified seeds or seedlings from a nursery.

7. What varieties grow best in the UK?

Musselburgh, Porbella, Jolant, Bandit, Oarsman.

8. How long do leeks take to grow?

Usually 5–7 months from seed to harvest.

9. Should I feed leeks while growing?

Yes — use a liquid feed every few weeks for thicker stems.

10. Can I leave leeks in the ground over winter?

Yes — they’re frost-hardy and store well in soil until needed.