PlantAlong

What to plant with basil

Only one pairing has been tested in a study; the rest are guidance or tradition.

Pairings
1
Last reviewed
Photo: Honglei Yue / Pexels
Good neighbors first, then plants to keep apart. Each one says how strong the evidence is.

Disputed

  • Tomatoes Tested in a study

    Claims: basil raises combined yield, improves tomato flavour and masks tomatoes from thrips and hornworms. Garden-scale trials found no consistent flavour effect and mixed yield results.12345

    Bomford 2004 thesis (not peer reviewed): basil companions gave a mean 20% relative-yield advantage, largest at high density and high basil share; no consistent taste preference. Bomford & Butler 2003 abstract: no LER significantly above 1; tomato pests did not respond. Penn State says basil masks tomatoes from thrips and hornworms but cites no study. Conboy 2019 (glasshouse): a marigold mix that included basil reduced whitefly; basil alone untested.

Sources

  1. West Virginia University, Plant and Soil Science (Ph.D. thesis); record on Organic Eprints, Yield, pest density, and tomato flavor effects of companion planting in garden-scale studies incorporating tomato, basil, and Brussels sprout, 2004 (deposited 19 Dec 2005). Retrieved 2026-11-02.
  2. Meeting abstract (ASA-CSSA-SSSA 2003 annual meetings abstracts collection, mirrored by Prince of Songkla University library), Do Tomatoes Love Basil But Hate Brussels Sprouts? Evaluating Popular Companion Planting Claims in Garden-Scale Studies (NE_05-bomford156693-oral), 2003. Retrieved 2026-11-02.
  3. Penn State Extension, Herbs Make Good Plant Partners and Companions, Updated April 22, 2026. Retrieved 2026-11-02.
  4. PLOS ONE 14(3): e0213071, Companion planting with French marigolds protects tomato plants from glasshouse whiteflies through the emission of airborne limonene, March 1, 2019. Retrieved 2026-11-02.
  5. University of California Agriculture and Natural Resources (UCCE Master Gardener Program), Companion Planting Chart: Companion planting in the vegetable garden, File dated 2023-09 in URL path; no date printed. Retrieved 2026-11-02.