Companion planting is the gardening practice of growing certain plants near each other for mutual benefit — the idea that some plants help one another grow, deter pests, or make better use of space when paired thoughtfully, while some combinations are best avoided.
Well-known examples include planting marigolds among vegetables (their scent is thought to deter some pests), basil near tomatoes, and the 'Three Sisters' of sweetcorn, beans and squash grown together. Aromatic herbs and pest-confusing flowers are popular companions throughout the veg patch.
Companion planting blends traditional wisdom, observation and some science — results vary and not every claimed pairing is proven, so treat it as a helpful, low-risk thing to experiment with rather than a guarantee. It's a fun way to plan a productive, biodiverse plot. Our free planting record and gardening journal help you plan and record what works in your garden.