Cucumber plant gaebb9dcdf 1920
By David Domoney

Companion planting is a traditional way of gardening, using plants to work together to improve the health of others when grown nearby.

There are several ways this can work, and it can even lead to better tasting crops.

Make a sacrifice

Sacrificial crops are exactly what they sound like. Provide plants for pests to eat so they don’t want to dine on your crops.

For example, cabbage white caterpillars like munching on cabbages and other brassicas as well as turnips and swedes. If you plant Tropaeolum majus (nasturtiums) nearby as a sacrificial crop, they will choose the bright flowers over the cabbages, keeping your harvest safe.

Companion planting
Nasturtiums could save your cabbages

Plant these flowers near Brussels sprouts too, because caterpillars and cabbage root fly quite like sprouts. Another way to keep your sprouts safe and secure is to plant Calendula officinalis (pot marigold) to attract slugs. Once the slugs make their way to the marigolds, you’ll be able to see their trails so you can physically remove them.

Another top tip is to plant bright flowers around crops to attract beneficial insects that will prey on any aphids.

Stay away

Repel pests by planting strong-smelling plants that will mask the smell of their favourite crops.

Marigolds will deter whitefly from cucumbers and hopefully repel aphids from runner beans, whilst attracting lacewings and ladybirds that will prey on aphids.

Companion planting 2
Send carrot fly into a spin with garlic chive

Allium tuberosum (garlic chive) has a strong fragrance which will confuse the carrot root fly when planted near carrots. Planting garlic chives means you also have an easily accessible stock of chives to use in the kitchen for an extra boost of flavour.

Invite wildlife in

Encourage beneficial bugs into your garden to feast on pests. For example, lavender is a win-win as it has beautiful flowers that pollinators will also enjoy, and a fragrance that’s delightful to us but is a deterrent for aphids. Plant lavender next to leeks and carrots to confuse the aphids.

Lavender acts as an aphid deterrent

Put it to practice

Here are a few common crops to use as companions in the garden:

  • Plant leeks with carrots, celery, onions and spinach for improved growth. But, steer clear of planting them near beans and peas. The leeks will benefit the other veg by repelling carrot root fly.
  • Potatoes thrive when planted near marigolds, cabbage, and beans because they improve the growth and taste. However, keep them away from cucumbers and squash because they can become more susceptible to blight.
  • Grow the best onions by growing carrots, lettuce, and cabbage nearby, but avoid planting beans and peas nearby because onions release a chemical that can inhibit nitrogen production by the beans and peas.
  • Pea-family plants such as lupins, beans, peas, and sweet peas benefit the soil as they take nitrogen from the air and store it in their roots. Beans are generally suggested as a companion for many leafy nitrogen loving vegetables such as cucumbers, corn, and broccoli.

Make the most of your harvest using this guide to companion planting and your veg will be growing its best.

* David Domoney is a Thrive Ambassador and Chartered Horticulturalist. He also stars in ITV's Love Your Garden.

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