Companion Planting Chart: The Best Vegetable Pairings for Allotments
Companion planting is a tried-and-tested way to make the most of your allotment space, boost plant health, and get better harvests. By choosing the right plant partners, you can naturally deter pests, improve soil fertility, and even enhance the flavour of your crops.
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What is Companion Planting?
Companion planting simply means growing certain plants together because they help each other in some way—whether it’s deterring pests, attracting pollinators, or improving growth. For allotment gardeners, it’s a smart, organic way to get more from your plot without relying on chemicals.
The Essential Companion Planting Chart
Here’s a quick reference chart for some of the most popular allotment crops:
| Vegetable | Best Companions | Avoid Planting With |
|---|---|---|
| Carrots | Onions, Leeks | Dill |
| Beans | Sweetcorn, Cabbage | Onions, Garlic |
| Tomatoes | Basil, Marigold | Potatoes |
| Lettuce | Chives, Carrots | Parsley |
| Cabbage | Beans, Celery | Strawberries |
| Peas | Carrots, Turnips | Onions, Garlic |
| Potatoes | Beans, Horseradish | Tomatoes, Pumpkins |
| Courgettes | Nasturtiums, Corn | Potatoes |
Tip: Print this chart and keep it in your shed or greenhouse for easy reference!
Why These Pairings Work
- Carrots & Onions: Onions repel carrot fly, while carrots deter onion fly—plant them in alternate rows for best results.
- Tomatoes & Basil: Basil improves tomato flavour and helps repel whitefly and aphids.
- Beans & Cabbage: Beans fix nitrogen in the soil, which leafy crops like cabbage love.
Plants That Don’t Get Along
Just as some plants are best friends, others are natural enemies. Avoid planting:
- Onions with beans: Onions can stunt bean growth.
- Tomatoes with potatoes: Both are prone to blight and can spread it to each other.
- Carrots with dill: Dill can attract carrot fly.
Mistakes to Avoid
- Planting the same family in the same spot each year—rotate crops to prevent disease.
- Overcrowding—give each plant enough space for air circulation and healthy growth.
- Ignoring soil needs—some companions have different requirements, so check before planting.
Beyond Vegetables: Flowers and Herbs
Don’t forget about flowers and herbs! Marigolds, nasturtiums, and calendula attract beneficial insects and deter pests. Chives, mint, and rosemary add flavour to your kitchen and health to your garden.
Not sure what to plant together this month? Use our Month-by-Month Companion Planting Planner to stay organised.
Struggling with slugs? Read our Ultimate Guide to Companion Planting for Slug Control for natural, chemical-free solutions.