Guide to Companion Planting on Your Allotment

Companion planting is a traditional gardening method that pairs plants strategically to support their growth, deter pests, and boost overall yields. For allotment gardeners, where space is often limited, it’s an invaluable technique that not only maximizes productivity but also promotes a balanced, sustainable ecosystem.

This guide combines practical advice, plant pairings, and tips for success to help you master the art of companion planting on your allotment.

What Is Companion Planting?

Companion planting involves growing specific plants together to create mutually beneficial relationships. Some plants deter pests, others enhance soil health, and many attract pollinators or beneficial insects. By understanding these relationships, you can make better use of your allotment space while minimizing the need for chemicals and fertilizers.

Benefits of Companion Planting

1. Pest Control: Plants like marigolds and garlic repel common pests, keeping your crops healthy.
2. Improved Growth: Certain plant combinations, such as carrots and onions, grow better together because they don’t compete for nutrients and protect each other from pests.
3. Enhanced Pollination: Flowers like borage and zinnias attract pollinators that increase the yield of fruiting vegetables.
4. Weed Suppression: Ground-hugging plants like nasturtiums shade the soil, preventing weed growth.
5. Soil Health: Legumes, such as beans and peas, enrich the soil by fixing nitrogen, benefiting neighboring plants.

Companion Planting in Action: Top Combinations

Classic Vegetable Pairings

1. Tomatoes and Basil
   • Basil deters pests like whiteflies and aphids while enhancing the flavor of tomatoes.
   • Avoid planting tomatoes near potatoes to reduce the risk of blight.
2. Carrots and Onions
   • Onions deter carrot root flies, while carrots repel onion flies. Together, they form a pest-resistant partnership.
3. Beans and Sweetcorn
   • Beans fix nitrogen into the soil, while sweetcorn acts as a natural trellis for climbing beans.
4. Cabbage and Dill
   • Dill attracts predatory insects, like parasitic wasps, that feed on pests targeting brassicas.
5. Radishes and Cucumbers
   • Radishes repel cucumber beetles and act as a fast-growing trap crop.

The Three Sisters: Squash, Beans, and Corn

This Native American technique is a time-tested example of companion planting.

• Corn provides vertical support for climbing beans.
• Beans enrich the soil with nitrogen, aiding the corn and squash.
• Squash spreads across the ground, suppressing weeds and retaining soil moisture.

Flowers and Herbs as Companions

1. Marigolds
   • Emit chemicals that repel aphids, nematodes, and other pests.
   • Plant them around the edges of your allotment for protection.
2. Nasturtiums
   • Attract pests like aphids away from crops such as beans, squash, and cabbages, acting as a sacrificial trap crop.
3. Borage
   • Attracts pollinators and deters tomato hornworms. Its edible flowers are an added bonus!
4. Thyme and Cabbage
   • Thyme repels cabbage moths and enhances the flavor of brassicas.
5. Chives
   • Repel aphids and improve the flavor of carrots when planted nearby.

Fruits and Perennials

1. Raspberries and Comfrey
   • Comfrey serves as a living mulch and provides a nutrient boost when its leaves decompose.
2. Blueberries and Azaleas
   • Both thrive in acidic soil, and azaleas attract pollinators that benefit blueberry flowers.
3. Grapes and Hyssop
   • Hyssop attracts beneficial insects and repels pests that harm grapevines.

Unusual Companion Planting Ideas

1. Celery and Cauliflower
   • Celery deters whiteflies, which commonly attack cauliflower.
2. Brussels Sprouts and Mustard
   • Mustard acts as a trap crop, luring pests away from Brussels sprouts.
3. Chili Peppers and Okra
   • Chili peppers deter pests that feed on okra plants.

Plants to Avoid Pairing Together

While many plants work well together, some combinations can be problematic:

• Tomatoes and Potatoes: Both are prone to blight, which can spread quickly.
• Carrots and Dill: Dill can stunt carrot growth, despite its benefits for other crops.
• Beans and Onions: Onions release compounds that inhibit the growth of beans and peas.

Designing Your Allotment Layout

1. Layering Crops:
   • Use taller plants like sweetcorn or sunflowers to provide shade for heat-sensitive crops.
2. Trap Crops:
   • Dedicate part of your allotment to sacrificial plants like nasturtiums or mustard to lure pests away from your main harvest.
3. Pollinator Zones:
   • Incorporate nectar-rich flowers like lavender, cosmos, and zinnias to attract bees and other beneficial insects.
4. Crop Rotation:
   • Rotate your plant families each year to prevent soil depletion and minimize the spread of pests and diseases.

Tips for Successful Companion Planting

• Start Small: Experiment with a few pairings before expanding.
• Observe and Adjust: Every allotment is different, so monitor how your plants interact and adapt your plan accordingly.
• Keep Notes: Record your successes and failures to refine your approach over time.
• Encourage Biodiversity: The more diverse your planting, the better your allotment will support beneficial insects and deter pests.

Conclusion

Companion planting is an art and science that can transform your allotment into a thriving, productive space. Whether you’re planting the Three Sisters, pairing flowers with vegetables, or experimenting with herbs as natural pest repellents, the possibilities are endless.

By adopting companion planting principles, you’ll not only grow healthier crops but also contribute to a more sustainable gardening practice.

Happy planting!