Tomatoes may be the undisputed star of the summer garden, but they rarely thrive alone. The right companion plants can improve tomato health, reduce pests, attract pollinators, and even enrich the soil. While companion planting has long been rooted in tradition, recent research offers evidence-based insight into which pairings truly work. This guide explores over 20 proven companions for tomatoes, categorized by their function in the garden.
Pest-Repelling Companions
Some plants protect tomatoes by confusing or repelling common pests through strong scents or decoy tactics.
-
Thyme: Helps deter tomato hornworms and serves double duty as ground cover and a culinary herb.
-
Nasturtium: A classic trap crop that attracts aphids and whiteflies away from tomatoes, often used as a living pest barrier.
-
French Marigold: Emits root exudates that suppress root-knot nematodes in the soil. Choose low-growing varieties that won’t compete for light.
-
Cowpeas: Effective in drawing away stink bugs, acting as a diversionary host plant.
-
Radishes (especially fast-maturing types): Attract flea beetles, protecting tomato seedlings during early growth stages.
-
Collards: Used as a sacrificial plant to lure Harlequin bugs. Particularly effective in hot climates.
-
Basil: May help mask tomato scent from certain insects and improve airflow when planted with spacing in mind.
Pollinator and Beneficial Insect Attractors
These companions bring in insects that either assist with pollination or prey on common tomato pests.
-
Fennel & Dill: Their umbrella-shaped flower heads attract predatory wasps and parasitic insects that feed on tomato hornworm larvae. Plant at a distance, as fennel can be allelopathic.
-
Oregano & Marjoram: Let a portion go to flower—these long-blooming herbs draw beneficial insects like hoverflies and lacewings.
-
Cilantro: Especially valuable when allowed to bolt. Its flowers attract ladybugs and syrphid flies, which feed on aphids.
-
Sweet Alyssum: A low-growing flower that attracts parasitic wasps known to suppress tomato fruitworm populations.
-
Sunflowers: Their large blooms bring bumblebees, which aid in tomato pollination by buzz pollination. Also useful in attracting leaf-footed bugs away from the main crop.
-
Bachelor’s Buttons (Cornflower): Known to attract a broad range of pollinators, especially bees, enhancing overall garden fertility.
Soil-Enriching and Protective Plants
These species improve soil structure, fix nitrogen, or serve as cover crops to prevent erosion and suppress disease.
-
Fava Beans: Excellent nitrogen fixers. Grow in cool seasons and cut back before flowering to enrich the soil for spring-planted tomatoes.
-
Crimson Clover: A beautiful and efficient nitrogen fixer, ideal for cover cropping and interplanting between tomato rows.
-
Winter Rye & Oats: Cold-hardy cover crops that can be terminated and laid down in spring to suppress weeds and add organic matter.
-
Mustard Greens: When tilled into the soil, they release compounds that reduce fungal pathogens and nematodes—an effective green manure.
Companion Planting in Containers
Even in small spaces, strategic pairings can make a big impact. For container-grown tomatoes:
-
Compact Marigolds or Basil: Work well in shared pots.
-
Low-maintenance herbs: Such as thyme or oregano, offer pest resistance and culinary benefits without overwhelming the container.
Good soil and organic compost remain key to successful container companion planting.
Final Thoughts
Companion planting is more than folklore—it’s a practical and proven way to boost tomato health and productivity. Whether aiming to reduce pests, attract pollinators, or revitalize the soil, there's a companion plant suited to nearly every growing condition. By creating thoughtful plant pairings, gardeners can cultivate a more resilient and harmonious garden, with tomatoes thriving at its center.
