How Far Apart to Plant Leeks: The Perfect Spacing Guide for UK Gardeners

Introduction

Getting leek spacing right is crucial to growing thick, healthy stems and ensuring good airflow, disease resistance, and ease of harvest. Whether you’re growing a few rows in a raised bed or dozens on an allotment, knowing how far apart to plant leeks is key to leek-growing success.

In this guide, we’ll walk you through the ideal planting distances for leeks in the UK, including row spacing, spacing in raised beds and containers, and how different spacing affects the size and shape of your harvest. Plus, we’ll cover companion planting, common mistakes, and top tips for getting that perfect pencil-thick transplant spacing every time.

Ideal Spacing for Leeks (Quick Reference)

Adjust spacing based on the variety and your garden layout — tighter spacing means thinner leeks, while wider spacing allows for thick, show-quality stems.

Why Leek Spacing Matters

✅ Encourages thicker stems
✅ Improves air circulation (reducing disease risk)
✅ Makes weeding and watering easier
✅ Helps avoid root competition
✅ Affects how many leeks you can grow in a given area

Leeks grown too closely will compete for light and nutrients, resulting in thin, underdeveloped stalks.

The Best Planting Method: Dibbing and Dropping

In the UK, the traditional method for planting leeks involves:

• Making deep holes (15–20cm deep) with a dibber
• Dropping one seedling into each hole
• Watering into the hole (without backfilling)
• Allowing soil to settle naturally around the roots

This method works best when leeks are spaced 15cm apart in rows 30cm apart, allowing for straight, tall, white stems.

Spacing in Different Growing Setups

🌿 In Garden Beds or Allotments

• Standard spacing: 15cm between plants, 30cm between rows
• Ideal for traditional in-ground beds
• Easy to hoe, weed, and water between rows

🧱 In Raised Beds

• Tighter spacing works: 12–15cm both ways in a grid pattern
• Utilises space efficiently
• Great for succession planting or companion planting

🪴 In Containers or Grow Bags

• Use deep containers (at least 30cm depth)
• Space 10–15cm apart depending on desired size
• Ensure good drainage and regular feeding

Adjusting Spacing Based on Purpose

How Many Leeks Can You Fit in 1m²?

With standard spacing:

• 15cm x 15cm grid spacing
• You can fit approximately 36–40 leeks per square metre

For tighter spacing (10cm x 10cm), you could fit up to 80 leeks, but they will be smaller — ideal if you want slender baby leeks.

What Happens If You Plant Leeks Too Close?

🚫 Overcrowding causes:

• Thin, underdeveloped stems
• Increased competition for nutrients and water
• Higher risk of fungal disease due to poor airflow
• More difficulty weeding and harvesting

Thin leeks are fine for soups, but not great if you want thick, tender white stems.

Can You Plant Leeks Closer and Then Thin Them?

Yes — some gardeners plant seedlings closer together and thin them out as needed. This gives:

✅ Early harvest of baby leeks
✅ Extra time for remaining leeks to thicken up
✅ Flexible use of space

Just be sure to harvest some early, so remaining plants can fill out.

Spacing Tips for Success

• Use a measuring stick or planting board for accurate row spacing
• Plant in a staggered grid for maximum space efficiency
• Mark your rows with string to keep everything tidy
• Use dibber marks or pegs to keep spacing consistent

Companion Plants and Leek Spacing

Leeks pair well with:

Avoid planting too close to peas or beans, which dislike alliums.

Common Mistakes in Leek Spacing

Leek spacing is a balance — not too crowded, but not overly generous either.

Do You Need to Thin Out Leek Seedlings Before Planting?

Yes — thin and separate before transplanting to avoid planting multiple seedlings in the same hole. Choose strong, pencil-thick seedlings spaced correctly for best results.

How to Space Leeks for Succession Planting

• Stagger sowing times every 2–3 weeks
• Plant early varieties closer together (12cm)
• Plant late-season overwintering varieties wider apart (15–20cm)

This gives you a steady harvest from autumn through spring.

Conclusion

Proper spacing is one of the most important (and overlooked) parts of successful leek growing. Whether you’re aiming for show-stopping giant leeks or a tight bed of baby stems for soup, knowing how far apart to plant leeks can make all the difference.

Stick to 15cm between plants and 30cm between rows as a starting point, adjust based on your goals, and enjoy thick, flavour-packed leeks all winter long.

Top 10 Questions and Answers About Leek Spacing

1. How far apart should I plant leeks in rows?

Standard spacing is 15cm between plants, and 30cm between rows.

2. Can I plant leeks closer together?

Yes — for baby leeks or small garden spaces, use 10–12cm spacing.

3. How deep should I plant leeks?

Use a dibber to make holes 15–20cm deep, and drop seedlings in without filling.

4. Can I plant leeks in containers?

Yes — use a deep pot (30cm+) and space 10–15cm apart.

5. How many leeks can I plant per metre?

Roughly 36–40 leeks per m² with 15cm spacing.

6. Do leeks need thinning?

If planted closely, yes — harvest some early to allow others to grow thicker.

7. Will leeks grow if they’re too close?

Yes, but they’ll be thin and may suffer from poor airflow and disease risk.

8. Can I use tighter spacing in raised beds?

Yes — a grid pattern of 12–15cm spacing works well.

9. Do large leeks need more space?

Yes — space 20–25cm apart for large or exhibition-quality leeks.

10. Is spacing really that important for leeks?

Yes — it impacts size, health, ease of harvest, and flavour quality.