The 21 Best (and 7 Worst) Companion Plants for Tomatoes (2024)

Companion planting is the practice of planting specific crops in close proximity to each other to enhance nutrient uptake, provide pest control, encourage pollination, and increase crop production.

Seasoned gardeners have determined that certain plants improve the growth of tomatoes by repelling ​insect pests and tomato plant diseases, while others are best kept at a distance.

Learn which herbs, flowers, and root vegetables make the best and worst tomato companion plants.

What Is Companion Planting?

Companion planting is the practice of partnering plants so some benefit is gained from growing near one another or from succession planting (staggering crop plantings). It is also known as interplanting, intercropping, or creating a polyculture.

What Are the Benefits of Companion Planting?

Plenty of companion plants offer multiple benefits for tomatoes, such as repelling pests, aerating soil, and attracting beneficial insects. Before adding companion plants, make sure they flourish in the same garden conditions as tomatoes: full sun and rich, well-drained soil.

Strongly scented herbs may help repel insect pests, while flowers attract pollinators. Tomatoes are self-fertile, so even without pollinators, they can produce fruit. However, they produce a bigger harvest when pollinators are involved.Low growing herbs serve as living mulch and work well planted with tomatoes in pots. Root crops help aerate soil, allowing healthier tomato root development, while some also repel small pests. Certain ornamentals even attract beneficial insects that prey on insect pests. Generally, companion plants:

• Efficiently uses available space
• Improves soil
• Organic insect and disease controls
• Living mulch as sustainable weed control
• Attracts pollinators
• Improves health of one or both plants
• Provides a second edible crop

A few companion plants, considered trap crops, may have to be sacrificed for better tomatoes. More often, a tomato companion is also harvested and edible. Consider what your tomatoes need most and experiment with different companion plants to learn what gives the best results.

Best Tomato Companion Plants to Repel Harmful Insects

Calendula

Calendula emits a woody, musky fragrance that repels hornworms. The bright orange and yellow flowers are edible and work nicely in salads. They also help repel rabbits, aphids, flea beetles, nematodes, and corn earworms.

Chives

Chives are an edible, perennial herb that repel aphids, nematodes, and spider mites. When allowed to flower, they also attract pollinators, including butterflies, bees, and beneficial wasps.

Black-Eyed Peas

Black-eyed peas act as a trap crop to lure southern green stink bugs away from tomato plants. These peas are prolific producers, so you'll probably still get a harvest.

Radishes

Radishes trap flea beetles that web leaves and defoliate young tomato plants. They grow in shallow soil and don't interfere with tomato roots, so place them right at the base of the tomato plant. Infestations can lead to crop loss so pairing them with tomatoes may mean sacrificing this radish crop.

Sage

Sage is a fragrant herb with a strong musky scent that repels slugs, flea beetles, and spider mites. Blooms attract pollinators including butterflies and bumblebees. Note that sage needs drier conditions than tomatoes require, so plant in pots and place around your garden.

French Marigolds

French marigolds repel root-knot nematodes in soil and grow well with tomato plants in containers. They also deter tomato hornworms and aphids, and they can also serve as a trap crop for other pests. The cheerful orange and yellow flowers are edible and add a peppery flavor to salads.

Nasturtiums

Nasturtiums acts as a trap crop for pests, attracting aphids and whiteflies away from tomatoes, which reduces the spread of fungal disease. They also attract pollinators and hoverflies, which feast on aphids. Both leaves and flowers add peppery flavor to fresh and cooked dishes. The seed pod can be pickled as a substitute for capers.

Best Tomato Companion Plants to Increase Beneficial Insects

Cilantro

When allowed to flower, cilantro attracts parasitic wasps that feed on adult hornworms. This cool season herb also repels Colorado potato beetle, which arrives early in the garden. Fragrant and edible, cilantro is a favorite ingredient in salsa. Note that cilantro is a cool season crop while tomatoes are warm season. In order to reap the benefits, let the plants go to flower so that helpful insects will be attracted in the summer.

Oregano

Flowering oregano attracts the green lacewing, a voracious predator of insect pests in tomatoes. It also serves as shelter for ladybugs. Flowers attract pollinators and edible foliage is an excellent pairing with Mediterranean dishes. Oregano requires drier conditions than tomatoes, so to add it in, plant oregano in pots and place them around the garden.

Parsley

Flowering parsley attracts ladybugs, a top consumer of aphids. They also eat hornworm eggs. Parsley works as a living mulch for tomatoes and is an edible herb used in a wide variety of dishes. Parsley also grows well in pots. Like cilantro, parsley is a cool season crop. When used as a companion plant to warm season tomatoes, let it go to flower.

Best Tomato Companion Plants for Weed Control

Crimson Clover

Crimson clover is an excellent living mulch for tomatoes and the rest of the garden, too. It can be tilled under or worked into soil to replace depleted nitrogen. This plant is a standard in permaculture and attracts pollinators.

Best Tomato Companion Plants to Increase Pollination

Lavender

Lavender flowers are a favorite of bumble bees that buzz tomato flowers releasing pollen to aid fertilization. Both foliage and flowers have a sweet floral fragrance unattractive to flea beetles and nematodes but generally appealing to humans. Since lavender needs dry, sandy soil unlike tomatoes, grow in pots nearby.

Sunflowers

Sunflowers attract native bees, including bumble bees, to encourage tomato pollination. Many varieties are also visited by small birds who feed on insect pests in the garden.

Zinnias

Zinnias bring more color to a garden than almost any other bloom. Pollinators and predators flock to these flowers in pinks, oranges, reds, purples and yellows.

Best Tomato Companion Plants to Improve Tomato Health

Asparagus

Asparagus releases a compound toxic to root knot nematodes to help prevent chlorosis, stunting and wilting in tomato plants. It produces a natural fungicide that help prevent early blight and botrytis. Additionally, tomatoes produce solanine, which repels asparagus beetle. It's a perfect symbiotic relationship.

Basil

Basil increases root size for more fruit development. Its strong scent comes from essential oils that repel insect pests, including aphids, whiteflies, and hornworms. The fragrance masks the scent of the tomato plant, making it harder for pests to find the host plant to lay eggs.

Borage

Borage is a source of B vitamins, beta-carotene, calcium, choline, and trace minerals that improve soil for better tomato health. It also repels hornworms, attracts bumble bees and honeybees, and can work as a living mulch in the tomato patch.

Carrots

Carrots aerate soil around tomato roots contributing to better root health. Short varieties work best, as longer carrot types may not reach full size. Either way, carrots will still be edible.

Garlic

Garlic strong scent, along with antibacterial and antifungal compounds, make this member of the allium family a super pest deterrent and natural remedy for soil borne disease.

Best Plants to Grow in Containers with Tomatoes

Sweet Allysum

Sweet alyssum is popular as both filler and ground cover and works well potted with tomatoes. Flowers attract predators like parasitic wasps that eat pests such as aphids.

Thyme

Thyme is a fragrant, edible, low growing herb well suited to growing in tomato pots. The herb comes in many varieties including citrus scented types. Active compounds in it's essential oils repel ants, aphids, armyworms, grasshoppers, leafhoppers, and wireworms. Blooms attract native pollinators and parasitic wasps that feed on hornworms.

Worst Tomato Companion Plants

• Cole Crop (Brassica) family: Relatives of cabbage cultivars stunt the growth of tomato plants. Cole crops include broccoli, Brussels sprouts, cabbage, cauliflower, collards, ornamental kale, and kohlrabi,
• Fennel: Secretes a substance from its roots that inhibits tomato plant growth.
• Dill: Mature plants damage tomato roots causing stunting.
• Nightshades: Eggplant, peppers, and potatoes are all susceptible to early blight and late blight. Avoid planting them near each other and rotate these crops every three years. Tomato hornworms (Manduca quinquemaculata) decimate foliage and fruit of nightshade plants.
• Cucumbers: Cucumber mosaic virus and phytophthora blight affect both cucumbers and tomatoes and can spread from one crop to the other. Cucumbers can grow with tomatoes, as long as the gardener is planting tomato transplants and not growing from seed in the garden.
• Sweet Corn: Attracts corn earworm, the same pest as tomato fruitworm (Helicoverpa zea). Avoid growing plants in proximity susceptible to the same pests.
• Rosemary: Depletes soil nutrients needed to grow tomatoes. The two plants also require different soil types and growing conditions.