Planting herbs for pest control is a variation of companion planting, where you plant certain plants together to benefit each another. Herbs are a common companion to vegetable plants. While some herbs add nutrients to the ground that benefit the plants, others deter insects and animals that may cause damage. Herbs also attract beneficial insects to the garden that can help with pest control. Particularly fragrant herbs, such as lavender and thyme, repel pests by masking the appetizing scent of the vegetable flower the pest is searching for.
Plant basil in a row next to your tomatoes to deter mosquitoes and flies.
Plant coriander (cilantro) near plants susceptible to aphid infestations, such as leaf lettuce. This herb isn't bothered by aphids and repels them.
Plant garlic around fruit trees to deter borers. If planted near tomatoes, garlic may deter red spider pests.
Plant mint around your cabbages to keep cabbage worms away. Spearmint deters ants and aphids from nearby plants.
Plant oregano or sage with your broccoli and cabbages to repel the cabbage butterfly that lays eggs on the plants that lead to cabbage worm infestations. Sage is also good with carrots and protects them from flies.
Plant thyme near plants from the cabbage family to deter cabbage worms.
Plant the bitter herb horehound near tomatoes to deter grasshoppers and other leaf-eating insects; they find the herb's leaves distasteful. Horehound will also improve the tomato plants' growth.
Plant lavender in your flower beds to deter ticks and mice.
Plant rue near flowers or vegetables susceptible to Japanese beetle attacks, such as roses. Use caution, however, when handling this herb. Some people have allergic reactions to it similar to poison ivy.