The Best Companion Plants for Leeks and What to Avoid

Companion planting is one of the simplest ways to encourage healthy leek growth. I’ve been growing leeks for decades in my raised beds, and pairing them with the right neighbors always makes a difference. Leeks belong to the allium family (with onions and garlic), and their strong scent is a natural deterrent to pests like carrot fly. But not all plants get along with leeks—some compete for nutrients or invite unwanted insects.

Below is my guide to the best companions for leeks and what you should avoid.

Table of Contents

Best Companion Plants for Leeks

Carrots – Carrots and leeks make classic companions. Carrots repel leek moths, while leeks repel carrot flies. Plant them in alternating rows for best results.
Celery – Both like rich, moist soil, and celery benefits from the leek’s pest-repelling aroma.
Onions & Garlic – Fellow alliums that enhance pest control and grow well in similar conditions.
Cabbage Family (Cabbage, Broccoli, Kale, Brussels Sprouts) – Leeks help deter pests that target brassicas, including cabbage worms and flea beetles.
Beets – Beets don’t compete with leeks for nutrients and thrive side by side.
Strawberries – Leeks help repel slugs, which are common strawberry pests.

Plants to Avoid Near Leeks

Legumes (Beans and Peas) – These prefer lighter soil than leeks, and they don’t thrive in the same rich, moist conditions.
Asparagus – A heavy feeder that competes with leeks for nutrients and root space.
Sage and Other Strong Herbs – Can stunt leek growth and disrupt their flavor.
Parsley – Tends to compete with leeks for nutrients and space.

My Experience

In my garden, I’ve found carrots and leeks to be a winning combination year after year. I plant them in alternating rows, and the difference in pest damage is remarkable—much less carrot fly damage when leeks are nearby. I avoid beans in my leek beds since they struggle in the rich, damp soil leeks love.

Leek Companion Planting Chart

Plant Type	Good Companions	Bad Companions	Notes
Root Crops	Carrots, Beets	–	Carrots repel leek moths; leeks repel carrot flies.
Alliums	Onions, Garlic	–	Strengthen pest control; similar soil and water needs.
Leafy Vegetables	Celery, Cabbage, Kale, Broccoli, Brussels Sprouts	Parsley	Leeks help deter cabbage pests; avoid parsley due to nutrient competition.
Fruits	Strawberries	–	Leeks repel slugs around strawberries.
Legumes	–	Beans, Peas	Prefer different soil and can hinder leek growth.
Perennials & Herbs	–	Asparagus, Sage, Strong Aromatic Herbs	Compete for nutrients or stunt leek growth.

🌱 Gardener’s Tip: Best and Worst Leek Companions 🌱

✅ Best Pairings: Carrots, onions, garlic, cabbage family crops, celery, and strawberries.
❌ Avoid Planting With: Beans, peas, parsley, asparagus, and strong aromatic herbs like sage.

Leeks thrive alongside crops that deter pests and share similar soil needs—while legumes and strong herbs often compete or stunt growth.