Companion planting is an organic method of planting beneficial plants together with the idea that they will assist each other in some way, like deterring pests, improving growth, enhancing flavour, attracting beneficial insects and fixing nitrogen. Just as we have good companions, there are bad companions as well. Some plants dislike each other, and shouldn’t be planted in close proximity.
The best thing about companion planting is that it increases the variety of life forms in your garden.
The Three Sisters …corn, climbing beans, and squash… is an ancient American Indian form of companion planting, in which the three types of plant are of mutual benefit to each other.
The beans fix nitrogen in the soil for the corn and the squash, the corn is a support for the bean vines, while the squash provides the mulch.
A border of hyssop planted around the cabbages will deter the cabbage moth, whilst grapevines planted with hyssop grow better.
Some Good Companions
Plant Horseradish along with your potatoes to keep away potato bugs. It’s invasive so plant in bottomless pots sunk into the ground.
Basil and tomatoes make good companions as basil improves their flavour and growth and also repels flies and mosquitoes.
Garlic - Roses benefit from garlic since it repels aphids. Also good for raspberries.
Let your Parsley go to seed as it will attract parasitic wasps, which are very beneficial.
Nasturtium will helps control squash bugs, cucumber beetles, and whiteflies. Use as a trap crop for aphids.
Catnip - Repels flea beetle, aphids, ants and weevils. Mice don’t like to be around it, but cats adore this plant.
Borage is good for attracting bees and more than 100 beneficial insects. Plant with tomatoes, squash and strawberries.
Chives - Carrots will grow better and improve in flavour when planted with chives.
Plant Marigolds among your tomatoes to ward off nematodes.
Sage will be beneficial for broccoli, cauliflower, rosemary, cabbage and carrots. Deters cabbage moth, beetles and carrot flies.
Chamomile - Cabbage and onions. Attracts hoverflies and wasps.
Some Bad Companions.
Cabbages: Rue or Garlic
Wormwood: all other plants. It is good planted in the hen house as it helps repel stickfast fleas.
Rue: Sage and Basil
Potatoes: Apples, cucumbers, cherries, pumpkin, tomatoes, rosemary and apples.
Garlic: Peas, beans, cabbages and strawberries.
Cabbages: Tomatoes, garlic, rue, strawberries.
Apricots: Sage, basil, tomatoes.
Strawberries: Cabbages, cauliflowers, brussel sprouts, gladioli, garlic, tomatoes, broccoli. They do however, do well in a pine needle mulch.
Tomatoes: Rosemary, fennel, apricots, strawberries, dill, potatoes.