Each spring as we make plans for planting our vegetable gardens, one of our guides is the ancient tradition of companion planting. Companion plants are mutually beneficial, helping each other by increasing nutrient uptake, pollination, productivity, or by controlling pests. You should also be aware that certain plants should not be planted near each other as they will hinder productivity.
Using companion plants to repel pests is part of a practice known as integrated pest management or IPM, which is a holistic approach to preventing plant damage. Using IPM techniques will almost always solve a pest problem and save you from having to use pesticides.
Further down the path of polyculture are practices such as intercropping and trap cropping, but today we’re going to keep it simple — sort of. A comprehensive exploration of companion planting would take a book-length post and we’re already late with this one, so we’ll stick to the most commonly planted vegetables.
Let’s start by saying if you could only plant one plant to prevent pest damage, that would be the marigold. This little soldier repels all manner of bad bugs. Plant lots of it around your vegetable garden. Nasturtiums are another star of pest control, as is oregano. You’ll start to see some patterns emerging as you learn more.
Companions: basil, parsley, tomato.
Pest control: marigold deters beetles.
Companions: beet (bush beans only), cabbage family, carrot, celery, chard, corn (see Three Sisters), cucumber, eggplant, pea, potato, radish, strawberry.
Pest control: marigold, nasturtium, rosemary and summer savory deter bean beetles.
Helpers: summer savory improves flavor.
Don’t plant near: garlic, fennel, onion and shallots.
Companions: bush bean, cabbage family, kohlrabi, lettuce, onion.
Helpers: catnip, mint. Garlic improves growth and flavor.
Don’t plant near: runner or pole beans (stunts growth) and mustard.
Cabbage Family: (bok choy, broccoli, Brussels sprouts, cabbage, cauliflower, Chinese cabbage, collard, kale, kohlrabi, rutabaga, turnips)
Companions: beet, celery, chard, lettuce, onion, potato, spinach.
Pest control: catnip, hyssop, mint, rosemary, sage, tansy and thyme deter cabbage moths. Mint deters ants. Nasturtium deters beetles and aphids. Tansy deters cutworm.
Helpers: chamomile and garlic improve growth and flavor. Dill improves growth and health. Mint improves flavor and health.
Don’t plant near: kohlrabi and tomatoes stunt each other’s growth.
Companions: bean, lettuce, onions, pea, pepper, radish and tomato.
Pest control: rosemary and sage deter carrot fly.
Don’t plant near: dill retards growth.
Companions: bean, cabbage family, tomato.
Pest control: chive, garlic and nasturtium deter aphids.
Companions: bean, cabbage family, and onion.
Companions: bean, cucumber, melon, parsley, pea, potato, pumpkin, squash.
Pest control: marigold and white geranium deter Japanese beetles.
Don’t plant near: tomato attracts the same worm.
Companions: bean, cabbage family, corn, pea, radish, tomato.
Pest control: marigold and nasturtium deter beetles. Tansy deters ants, beetles, bugs and flying insects. Oregano deters pests in general.
Helpers: nasturtium improves growth and flavor.
Don’t plant near: sage.
Companions: bean, pepper.
Pest control: marigold deters nematodes.
Helpers: tarragon, mint.
Companions: beet, cabbage family, carrot, onion, radish, strawberry.
Pest control: chives and garlic deter aphids.
Companions: corn, pumpkins, radish, squash.
Pest control: marigold and nasturtium deter beetles. Mint deters cabbage moth and ants. Oregano deters pests in general.
Helpers: mint improves flavor and health.
Companions: beet, cabbage, carrot, chard, lettuce, pepper, strawberry, tomato.
Helpers: chamomile and summer savory improve growth and flavor.
Companions: asparagus, corn, tomato.
Companions: bean, carrot, corn, cucumber, radish, turnip.
Pest control: chive deters aphids.
Helpers: mint improves health and flavor.
Don’t plant near: garlic and onion will stunt growth.
Companions: carrot, eggplant, onion, tomato.
Companions: beans, cabbage family, corn, eggplant, pea.
Pest control: marigold deters beetles. Horseradish provides general protection when planted at the corners of the potato patch.
Don’t plant near: tomatoes are attacked by the same blight.
Companions: corn, melon, squash.
Pest control: marigold and nasturtium deter beetles. Oregano provides general protection from pests.
Companions: corn, melons, squash.
Helpers: chervil and nasturtium improve growth and flavor.
Don’t plant near: hyssop.
Companions: cabbage family, strawberry.
Pest control: borage deters worms. Marigold deters beetles. Nasturtiums deters beetles and squash bugs. Oregano provides general protection.
Helpers: borage improves growth and health.
Companions: bean, lettuce, onion, spinach, thyme.
Pest control: borage improves resistance to insects and disease. A border of thyme will deter worms.
Don’t plant near: cabbage.
Companions: asparagus, carrot, celery, cucumber, onion, parsley, pepper.
Pest control: basil repels flies and mosquitoes. Borage deters tomato worm. Marigold deters nematodes and tomato worm and pests in general.
Helpers: Basil, bee balm, borage, chives, and mint improve flavor and growth.
Don’t plant near: corn attracts the same worm. Mature dill retards tomato growth (although young dill helps growth and health). Kohlrabi stunts tomato growth. Potatoes attract the same blight.
Many thanks to Cass County Extension where I got much of this information. If you want to know more about companion planting there are two book titles that I ran across over and over again while researching this post: Carrots Love Tomatoes: Secrets of Companion Planting for Successful Gardening by Louise Riotte and Great Garden Companions by Sally Jean Cunningham.
Apologies to folks in the warmer climes for not getting to this sooner, but there are still many tips that you can use this season.