Companion Planting: What Actually Works and What’s Folklore

Few topics in gardening generate as many confident charts as companion planting.

What companion planting actually means

Companion planting is growing different plants near each other so that one or both benefit.

What has good evidence

This is probably the most reliable form of companion planting.

The Three Sisters

The best-known companion planting is the Three Sisters: corn, beans and squash, grown together for centuries by many Indigenous peoples of North America.

What is partly true

Marigolds are probably the most famous companion plant, often said to repel nearly every pest.

What is mostly folklore

Many popular charts list detailed "friends" and "enemies" for each vegetable, with little explanation.

Real reasons to keep some plants apart

There are a few genuine incompatibilities worth knowing, but they are usually about shared pests, diseases or competition rather than mysterious dislikes.