Some plants do better when in the company of other plants. Companion planting is using this knowledge to increase plant performance.
Companion planting includes planting flowers, herbs or vegetables to repel or trap harmful insects.
It also includes using plants to attract useful insects which prey upon harmful insects. People use companion planting as a way of reducing chemical insecticide use. Companion planting requires some experimentation. What may be successful in one garden may not be successful in another garden. This may be caused by different microclimates, soil types, plant varieties and cropping practices.