Companion planting is a gardening technique that involves growing different plants together to boost growth, repel pests, and improve crop production. It’s based on the premise that some plants have natural relationships that benefit each other when planted in proximity. For example, some plants can release chemicals that deter pests, while others improve soil quality by fixing nitrogen or providing shade to their neighbouring plants. This method is typically used in gardening as a natural way to promote plant health without using pesticides or fertilizers.
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Tomatoes
Companion planting infographic for tomatoes
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Onions
Companion planting infographic for onions
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Peppers
Companion planting infographic for peppers
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Corn
Companion planting infographic for corn
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Garlic
Companion planting infographic for garlic
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Lettuce
Companion planting infographic for lettuce
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Broccoli
Companion planting infographic for broccoli
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Potatoes
Companion planting infographic for potatoes
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Carrots
Companion planting infographic for carrots
One of the most popular companion planting strategies is the "Three Sisters" method. In this system, corn, beans, and squash are planted together, the corn gives support for the beans to climb, the beans add nitrogen to the soil, and the squash acts as a ground cover to retain moisture and prevent weeds. Another well-known combination is planting basil near tomatoes, as basil is believed to improve tomato flavor and repels insects like aphids and hornworms. Marigolds are another beneficial companion plant, usually grown beside vegetables to help deter harmful nematodes and other insects.
Companion planting can also help prevent diseases by increasing biodiversity in the garden. When different species are mixed rather than planted by themselves, it becomes harder for pests and diseases to spread. Some plants, like Nasturtium (Tropaeolum), act as "trap crops," attracting pests away from more beneficial plants. This works well for controlling aphids and caterpillars in vegetable gardens.
By using companion planting strategies, healthier gardens can be created and become more productive, while limiting the need for chemical controls. Companion planting can lead to stronger plants, fewer pests, and a more sustainable garden.
Common companion plantings in gardens
Tomatoes + Basil
Basil helps repel pests like aphids and tomato hornworms, and some say it even improves tomato flavor.
Carrots + Onions
Onions repel carrot flies, and carrots help break up the soil for onions.
Corn + Beans + Squash (The “Three Sisters”)
Corn provides a natural pole for beans.
Beans fix nitrogen in the soil.
Squash shades the ground, preventing weeds and retaining moisture.
Marigolds + Most Veggies
Marigolds repel many insects and nematodes with their scent.
Broccoli + Nasturtiums
Nasturtiums act as a "trap crop" to lure aphids and other pests away from broccoli.