Getting Started

Companion Planting

Companion Planting
If you want to garden organically and ditch chemicals but still improve yields, companion planting is very important. It's all about establishing groups of plants that are beneficial to each other. An old idea, it was largely forgotten in the years where gardeners relied heavily on pesticides, but as more people want to go back to natural methods, companion planting has been rediscovered.
Some plants may protect crops from pests by repelling them or confusing them with their scent; others improve pollination by attracting bees and other pollinators; others encourage predators that eat pests. Some plants may also act as 'sacrificial plants' to attract pests away from crops.

As well as improving your crops, companion planting also makes your garden a much healthier, diverse ecosystem. By creating a favourable environment for your plants, you’ll enhance the entire food chain, with more insects, invertebrates, small mammals and birds.

Companion planting can be done in the smallest of spaces, even if you just have a couple of containers - a pot of tomatoes paired with basil will be beneficial to each other and look good.

Here are some successful companion plants - remember to plant them alongside the crops they are protecting:
  • Dill (Anethum graveolens): Attracts tiny beneficial wasps that control cabbage pests.
  • Sweet alyssum (Lobularia maritima): The tiny perfumed flowers attract many beneficial insects that prey on potato pests.
  • Nasturtium (Tropaeolum): Not only edible but one of the biggest pest attractors. Especially good around cucumbers, French and runner beans. Cabbage white butterflies will lay their eggs on Nasturtiums, keeping caterpillars away from brassicas.
  • Garlic chives (Allium tuberosum): Its strong scent confuses and deters the carrot root fly, which can normally smell carrots from up to a mile away.
  • Lavender (Lavandula angustifolia): Attracts bees, butterflies and hoverflies. Its strong scent can also deter aphids. Plant with carrots and leeks to confuse pests.
  • Wormwood (Artemisia absinthium): Its strong scent repels aphids and flea beetles and the yellow flowers attract hoverflies, lacewings and ladybirds.
  • French marigold (Tagetes paluta): Deters whitefly on tomatoes.
  • Pot marigold (Calendula officinalis): Lures aphids away from beans. Encourages ladybirds, lacewings and hoverflies to pollinate courgettes.
  • Sage (Salvia officinalis): The scent confuses brassica pests. Its blue flowers attract bees and hoverflies.
  • Borage (Borago officinalis): The attractive blue flowers are a magnet for pollinators. It can prevent attack from tomato hornworm and is said to improve the flavour of strawberries.
  • Thyme (Thymus vulgaris): Looks good as ground cover under roses and deters blackfly. Soak thyme leaves in water and spray on brassicas to prevent whitefly.
  • Fennel (Foeniculum vulgare): Produces yellow blooms that attract hoverflies, which prey on aphids.
  • Mint (Mentha spp.): Deters flea beetles on brassicas, carrot root fly, onion fly but grow in pots, as it is invasive.
  • Summer savory (Satureja hortensis): Helps to repel blackfly, a common pest of broads beans.Sweet peas (Lathyrus): Attracts pollinators to your runner beans (don’t eat pods of sweet peas though).
  • Basil (Ocimum basilicum): The strongly scented herb attracts greenfly and other aphids away from tomatoes. Basil reportedly improves tomato flavour.
  • Radishes: Attract leaf miners away from spinach, leaving the radish roots unharmed.
  • Chives and garlic: The alliums repels pests that eat rose petals and chrysanthemums.
  • Tomatoes: Repel the diamondback moth larvae, which eat cabbage leaves.

Mutually beneficial plant combinations:

  • Sweetcorn, squash and runner beans : The traditional Native American Indian growing system, known as the "Three Sisters". The runner beans grow up the sweetcorn stalks keeping them off the ground; the beans attract beneficial insects that prey on pests. The squash acts as a living mulch and spiny varieties deter predators.
  • Outdoor tomatoes and asparagus.
  • Borage and balm.
  • Carrots and spring onions: Sow spring onions among carrots - the smell of onion deters carrot root fly, while the scent of carrots wards off onion fly.
Carrots and leeks: The smell of leeks deters carrot root fly and carrots help to deter leek moth.

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