Find Companion Plants
Select your main crop to see what grows well nearby and what to avoid.
- Some pairings have solid research (basil + tomato, marigolds as nematode deterrents)
- Others are traditional wisdom — results vary by location and pest pressure
- Good soil and proper spacing matter more than any companion pairing
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What Is Companion Planting?
Companion planting is the practice of growing different plants near each other for mutual benefit — pest control, attracting pollinators, improving soil nutrients, or making better use of space. The most famous example is the Native American "Three Sisters": corn, beans, and squash grown together. Corn provides structure for beans, beans fix nitrogen, and squash leaves shade the ground to retain moisture.
Best Companions for Tomatoes
Tomatoes are one of the most studied crops for companion planting. Basil is widely recommended and may help repel thrips and aphids. Marigolds (especially French marigolds) release compounds from their roots that deter soil nematodes. Carrots and parsley also make good neighbors. Keep tomatoes well away from fennel, brassicas, and corn.
Plants That Should Never Grow Together
Fennel is notoriously incompatible with almost all garden plants — it releases allelopathic chemicals that inhibit nearby growth. Keep it isolated or in containers. Alliums (onion, garlic) inhibit beans and peas. Tomatoes and potatoes share diseases and should be kept apart.