What is companion planting?
It is the close planting of different plants that enhance each other’s growth or protect each other from pests. Companion planting will boost growth, repel pests, and improve flavors. Aside from the benefits to your plants, companion planting uses your garden space more efficiently, letting you harvest more. The diversity that companion planting provides is also good for pollinators, wildlife, and soil health.
Companion planting is one of the easiest ways to mimic a natural ecosystem more closely. There are many benefits you’ll see in your garden if you use companion planting.
Alyssum – Very attractive to pollinators, and useful as a mulch to keep weeds down between rows.
Agastache – Very attractive to bees. Plant a row away from the garden to lure cabbage moths away from Brassica crops. Do not plant near radishes.
Asparagus – Grow with Asters, Basil, Cilantro, Marigolds, Nasturtiums, Oregano,Parsley, Peppers, Sage, Thyme, Tomatoes. Asparagus repels nematodes that attack tomatoes, and tomatoes repel asparagus beetles. Do not grow with garlic, onions, potatoes.
Basil – Will improve vigor and flavor of tomatoes, planted side-by-side. Also good with asparagus, oregano, and peppers. Basil helps repel aphids, asparagus beetles, mites, flies, mosquitoes, and tomato horn worm.
Beans – Grow with Carrots, Cabbage, Cauliflower, Cucumber, Marigolds, Corn. Does not like onions, Chives, Leeks or Garlic. Beans also Fix nitrogen deficiency in soil. Pole beans and beets stunt each other’s growth.
Beets – Beet greens and scraps are very good for the compost, returning captured manganese and iron to the soil via the composting process. Plant with bush beans, Brassicas, corn, garlic, kohlrabi, leeks, lettuce, and mint. Avoid planting beets near pole beans.
Carrots – Plant with beans, Brassicas, chives, leeks, lettuce, onions, peas, peppers, pole beans, radish, rosemary, sage, and tomatoes. Avoid planting with dill, parsnips, and potatoes.
Catnip – Attracts pollinators, parasitic wasps. Catnip repels aphids, asparagus beetles, Colorado potato beetles, and squash bugs.
Cauliflower – Likes growing with Beans, Celery, Oregano. Avoid planting beside Nasturtium, Peas, Tomatoes or Potatoes.
Celery – Good partner for beans, Brassicas, cucumber, garlic, leek, lettuce, onion, and tomatoes.
Chives – Improves the flavor of carrots and tomatoes. A companion plant for Brassicas. Helps to repel aphids, carrot rust fly, and Japanese beetles. Avoid planting near beans and peas.
Garlic – Planting garlic near roses will help to repel aphids. Because of its sulfur compounds, it may also help repel whiteflies, Japanese beetles, root maggots, carrot rust fly, and other pests. Garlic, made into a spray, will act as a systemic pesticide, drawing up into the cells of the plants. It’s a good companion for beets, Brassicas, celery, lettuce, potatoes, strawberries, and tomatoes. Avoid planting it near peas or beans of any kind.
Kohlrabi – A worthy companion for beets, Brassicas, cucumbers, and onions. Avoid planting near peppers, pole beans, strawberries, and tomatoes.
Leeks – Grow with beets, carrot, celery, onions, and spinach. Leeks help repel carrot rust flies. Avoid planting near beans and peas.
Onions – Plant summer savory near onions to improve their flavor. Onions also work well alongside beets, Brassicas, carrots, dill, kohlrabi, leeks, lettuce, strawberries and tomatoes. Onions help to repel the carrot rust fly. Don’t plant onions near asparagus, or peas.
Parsley – Parsley likes asparagus, carrots, chives, corn, onions, and tomatoes. The leaves can be sprinkled on asparagus to repel asparagus beetles, and around roses, to improve their scent. Let some of your parsley go to bloom to attract predatory wasps. Don’t plant it near mint.
Peas – Excellent companions for beans, carrots, celery, corn, cucumber, eggplant, parsley, peppers. potatoes, radish, spinach, strawberries and turnips. Avoid planting peas near onions.
Peppers – Pepper plants make good neighbors for asparagus, basil, carrots, cucumbers, eggplant, endive, oregano, parsley, rosemary, squash, Swiss chard, and tomatoes. Never plant them next to beans, Brassicas, or fennel.
Potato – Bush beans, celery, corn, garlic, marigolds, onions, and peas all do well planted near potatoes. Avoid planting potatoes near asparagus, Brassicas, carrots, cucumber, kohlrabi, melons, parsnips, rutabaga, squash, sunflower, and turnips.
Radish – Plant radishes near beans, beets, celeriac, chervil, cucumber, lettuce, mint, parsnip, peas, spinach, squash, and tomatoes. Avoid planting near agastache or potatoes.
Rosemary – Rosemary is a good companion for beans, Brassicas, and carrots. Rosemary repels cabbage moths, bean beetles, and carrot rust flies.
Sage – Sage repels both the cabbage moth and the carrot rust fly, so it’s a great all around companion plant in the vegetable garden. Do not, however, plant it near cucumbers, which are sensitive to aromatic herbs.
Soya beans – Good for fixing nitrogen, and acting as a mulch against weeds. Grow with corn. Soya beans repel Japanese beetles and chinch bugs.
Spinach – A good companion for Brassicas, eggplants, leeks, lettuce, peas, radish, and strawberries, particularly. Don’t plant spinach near potatoes.
Squash – Companions: corn, lettuce, melons, peas, and radish. Borage is said to improve the growth and flavor of squash. Marigolds and nasturtium repel numerous squash pest insects. Avoid planting near Brassicas or potatoes.
Strawberries – Strawberries respond strongly to nearby plants. Couple them with beans, borage, garlic, lettuce, onions, peas, spinach, and thyme. Avoid Brassicas, fennel, and kohlrabi.
Summer Savory – This herb attracts honeybees, and repels cabbage moths. Planting it near beans and onions will improve the flavour of both.
Thyme – An all around beneficial plant for the garden, thyme is particularly worth planting near Brassicas (as it repels cabbage moths), and strawberries, as it enhances flavor.
Tomatoes & Basil – Tomatoes and basil not only work well together on the dinner table, but the pair are also excellent garden companions. Basil plants can help tomato plants overcome insects and disease and can improve the growth rate and flavor of tomatoes.
Herbs That Keep Insects Away
- Peppermint – repels ants, white cabbage moth, aphids, and flea beetle. Since Mint is a notorious spreader that can easily get out of control establish it in pots that are above ground or sunk below where roots can’t escape drainage holes.
- Garlic – discourages aphids, fleas, Japanese beetles, and spider mites.
- Perennial Chives – repel aphids and spider mites, two very common garden pests. Chives are often planted among roses to keep aphids away and to resist the Black Spot disease.
- Basil – drives away flies and mosquitoes.
- Borage – deters that monster of vegetable garden insects, the tomato hornworm.
- Rosemary and Sage – repel cabbage moth, bean beetles, and carrot flies.
- Annual Marigolds – can be used anywhere to deter Mexican bean beetle, squash bug, thrips, tomato hornworm, and whitefly. They are also known to repel harmful root knot nematodes (soil dwelling microscopic white worms) that attack tomatoes, potatoes, roses, and strawberries. The root of the Marigold produces a chemical that kills nematodes as they enter the soil. If a whole area is infested, at the end of the season, turn the Marigolds under so the roots will decay in the soil. You can safely plant there again the following spring.
- Nasturtium – is another annual, in this case a trailing vine that keeps away Colorado potato bug, squash bug, and whitefly.
- Radish – can be planted to discourage cucumber beetle, squash bug, and stink bug.