Companion planting

Definition

An agricultural and horticultural practice in which different plant species are grown in deliberate proximity to enhance ecosystem services, including biological pest control by attracting natural enemies, provision of floral resources for pollinators and parasitoids, habitat provision for beneficial arthropods, and disruption of host-finding cues for herbivorous insects. A form of polyculture that leverages plant-insect and plant-plant interactions to reduce reliance on chemical inputs.

Etymology

Example

Intercropping Brassica crops with dill (Anethum graveolens) attracts parasitoid wasps that attack cabbage aphids (Brevicoryne brassicae), while flowering strips of buckwheat (Fagopyrum esculentum) adjacent to vegetable fields support hoverfly (Syrphidae) populations whose larvae prey on aphids.

Synonyms

• Intercropping
• Polyculture

Related Terms

• Polyculture
• Biological control
• habitat manipulation
• trap cropping
• beneficial insects
• Parasitoid
• predator-prey interactions
• floral provisioning

Usage Notes

Distinguished from trap cropping, which uses attractive plants to concentrate pests away from the main crop; companion planting aims to suppress pests through attraction of natural enemies or repellence. Effectiveness varies with arthropod guild: generalist predators often respond to diverse vegetation, while specialist parasitoids may require specific host-plant complexes. The term is sometimes used loosely in gardening literature without mechanistic evidence; entomological applications increasingly emphasize tested plant-insect trait matching over traditional companion lists.