by Bethany Hayes
Companion planting is one way gardeners can naturally maximize their harvests and grow healthier plants with fewer pests and diseases. Tomato plants attract many pests and diseases, so using a variety of tomato companion plants is an excellent way to ensure these garden plants thrive.
Companion planting isn’t a new idea; gardeners and farmers have used these techniques for years. Nowadays, we know why certain plants are beneficial because science shows us that companion planting truly has benefits.
The remarkable thing is that there are plenty of suitable companion plants for tomatoes. Let’s take a look at some of the best choices.
26 Best Tomato Companion Plants
Tomato plants are friendly to many other plants, so picking tomato companion plants is easier than many other veggies in your garden. When selecting companion plants, make sure to consider what benefits you want to
Amaranth is a grain that you can grow in your garden. It makes an excellent tomato companion plant because it repels pests by attracting beneficial predatory insects.
One of the most common tomato companion plants is basil. It’s the most notable because the flavor combination is delicious, but basil also deters thrips and tomato hornworms. Both of those pests are severe problems to your tomato plants.
Basil plants belong on the companion plant list for many veggies because the plant releases volatile chemicals that mask the scent of plants that the pests enjoy. So, that means the pests aren’t able to find their desired plant to eat.
Borage attracts pollinating insects, so using it as a tomato companion plant ensures that your plants have all the pollinators needed. At the same time, borage helps improve the flavor of ripened tomatoes.
Another bonus of growing borage with tomatoes is that it acts as an organic repellant of hornworms and cabbage worms!
4. Bush Beans
Planting bush beans near your tomato plants helps to reduce diseases by increasing air circulation. Poor air circulation encourages fungal diseases because fungi live in damp, humid conditions.
Try interplanting tall tomato plants and shorter bush beans in between each one. This keeps plenty of space between the plants.
Bush beans aren’t the only crop that works for this! Short plants are ideal for this in general.
Most people never think of planting carrots near tomato plants, but carrots grow deep into the soil since they’re root crops. This helps to break up the ground near your carrot plants, aerating the soil and allowing nutrients, water, and oxygen to reach the roots of tomato plants.
Celery is a great companion plant for tomatoes because the root system loosens up the soil around the tomato plants, encouraging earthworms and other beneficial insects. Then, the worms release more nutrients into the ground.
Humans might debate over whether cilantro is delicious or not, but we know that many beneficial insects think this herb is incredible. For example, cilantro blooms are a nectar source for predatory insects that eat common tomato pests.
Plant a few around your garden and let them go to flower. You’ll be surprised by how few pests are in your garden.
8. Collard Greens
Are you struggling with harlequin bugs attacking your tomato plants? Collard greens are an excellent tomato companion plant to stop harlequin bugs from destroying your crops.
These pests live in warm regions throughout the United States, favoring cabbage family plants. Planting collard greens as a sacrificial trap crop lures the harlequin bugs away if they’re on your tomato plants. You won’t get to eat those collard green plants, but you won’t lose all of your tomato plants!
Many people call coneflowers echinacea, and these large, wide blooms invite bumblebees and other pollinators. Plus, they’re beautiful, improve pollination, and have other uses that you may enjoy.
Cowpeas fight against green stink bugs, a common southern pest that no one likes to handle. If you notice these pests near your tomato plants, try planting cowpeas!
You might think that green stink bugs aren’t a problem, but they feed on different fruits and vegetables, including tomatoes. All you have to do is plant cowpeas several feet away from your tomato plants. It’s best if you plant them several weeks before you plant tomatoes.
11. Crimson Clover
If you use crimson clover as a living mulch, it’s one of the best tomato companion plants. Try planting it between tomato rows or between tomato plants, letting it grow the entire season.
Crimson clover is a great companion plant because it competes with weeds and provides nitrogen into the soil. So, it fixes any nitrogen issues in surrounding plants.
Another reason it works well in your garden for tomato plants is because it attracts beneficial insects and pollinators.
Cucumbers tend to be on the bad list for many companion plants because these vegetables produce growth-inhibiting allelochemicals that dramatically reduce germination. So if you have to plant surrounding crops by seeds, avoid putting them near cucumbers, but tomato plants are transplanted.
Cucumbers have several benefits for tomato plants. Not only do the blooms attract a variety of pollinators, but bush cucumber plants act as a weed management tool.
Some tomato companion plants list dill as a wrong choice, but science shows us that dill is beneficial to tomato plants because dill attracts parasitic wasps. Parasitic wasps are beneficial insects that love to feed on tomato hornworms, tomato fruit worms, and other caterpillars.
Many of the most destructive pests in the garden are caterpillars!
Adding dill throughout your garden, including near your tomato plants, attracts all sorts of other beneficial insects, such as ladybugs, lacewings, minute pirate bugs, tachinid flies, and more.
14. Hairy Vetch
Never heard of hairy vetch? You aren’t alone; it’s not a common garden plant, but this is an excellent tomato companion plant if you struggle with tomato diseases like early blight or Septoria leaf spot.
Try planting a hairy vetch cover crop; this crop is proven to reduce foliar disease in tomatoes more than other methods! Hairy vetch is also a legume, so it adds nitrogen to the soil.
If you want to use this plant to add nitrogen to your soil, plant it in the fall and remove the plants by hand or cut them down when the first seed pods appear in late spring. Then, plant your tomato transplants in the cut-down hairy vetch. Doing this also suppresses weeds.
Growing lettuce between your tomato plants fills vacant spots and helps to protect the soil from erosion. In addition, lettuce loves the shade that tomato plants cast over them, so you’ll end up with an excellent lettuce harvest.
Another reason that lettuce is one of the best tomato companion plants is that it helps to regulate soil moisture. Tomato plants benefit from consistent soil moisture (but never soggy); it helps their growth.
Marigolds are one of the best tomato companion plants; they work as great companion plants for many different vegetables in your garden. I plant marigolds throughout my garden – you’ll reap so many benefits.
Marigolds give your garden pops of color and cheer, but at the same time, they counteract root rot that is caused by tomato worms and slugs. Many pests stay away from marigolds!
Nasturtiums are one of the most popular edible flowers, and they look lovely when planted in your garden. When planted near tomato plants, they act as a trap crop for aphids, luring the pests away from the plants you want to keep.
Plus, the flowers are tasty and make delicious additions to salads.
If you’ve never grown cover crops before, try oats! Oats are one of the best tomato companion plants for reducing weeds.
Plant oats in the fall, and when the freezing temperatures arrive, the plants die. In the spring, plant your tomato transplants into the decomposing oat plants. It’s a natural way to control weeds and protect your soil by forming a mat.
Another fantastic herb that is also a companion plant is oregano, and it belongs near your tomato plants. Let’s be honest; the flavor of tomatoes and oregano together is perfect!
Oregano works, but you have to let it go to flower. So I plant a few oregano plants that I trim and harvest throughout the growing season and a few that I let go to flower to attract different pest-eating beneficial insects.
Parsley works well when grown with tomatoes. This herb attracts hoverflies to your veggie garden, so try putting parsley throughout your garden beds. Hoverflies are beneficial insects that feed on destructive garden pests that you don’t want to have on your tomato plants.
I love radishes; they’re such an underrated plant that people seem to avoid growing. It’s because no one knows how to enjoy them. Radishes act as a trap crop for flea beetles, luring them away from your tomato plants. To make this work, they need to be planted adjacent to the tomato plants.
This works because flea beetles love to eat radish leaves more than tomato leaves. So they’ll munch on the leaves happily rather than destroying your tomato plants. This is truly important for young tomato plants that suffer the most from flea beetle infestations.
Sunflowers are lovely in any garden, and when you plant them near your tomato plants, they increase pollination rates. In addition, bumblebees love sunflowers, along with other pollinators and bee species. So, putting them near your tomato plants gives bumblebees plenty of nectar sources.
23. Sweet Alyssum
Sweet alyssum is best known for improving biological control when growing lettuce, but it’s also helpful when growing tomato plants. This herb produces small, white blooms that feed parasitic wasps and syrphid flies.
24. Sweet Potatoes
If you’re looking for tomato companion plants that reduce diseases, consider planting sweet potatoes nearby. Rather than using disease-fighting compounds, sweet potatoes reduce diseases by shielding the plants from any splashing diseases in the soil.
Many spores live in the soil, so it infects your plants when rain hits the dirt and splashes onto the leaves. This splashing is dramatically reduced by growing a thick cover of sweet potatoes over the soil around tomato plants. That means you will have fewer diseases to face.
Thyme is one of the best pest-busting companion plants out there, especially if you struggle with armyworms. Interplanting tomatoes with thyme reduces egg-laying by adult armyworms. Since these plants are a ground cover, you end up with a living mulch around your tomato plants.
The only downside is that thyme is a perennial, and tomato plants aren’t. So, you might have to keep adding new thyme plants each year.
26. Winter Rye
Winter rye isn’t a typical garden crop; it’s a cover crop that helps to reduce and smother weeds around your plants. Most gardeners plant winter rye as a winter cover crop that puts nutrients back into the soil and mows down in the spring when it starts to flower. Then, you plant your garden plants right into the mowed-down winter rye.
That’s not how you want to use it as a tomato companion plant.
Typically, you plant winter rye around the base of your tomato plants and let it grow, protecting the soil and regulating soil temperature.
5 Bad Tomato Companion Plants
While more plants work as companion plants than not, some plants make poor friends. So it’s always important to know who shouldn’t be your tomatoes’ friends when planning your garden.
Planting corn and tomatoes together is another no-no. Earworm pests love corn and, and they’re similar to tomato fruitworms. When situated close together, it makes them susceptible to the same pests.
Fennel is one of those plants that most cannot grow near because the plant releases a substance through the root system. If you plant fennel near tomatoes, chances are the growth of your plants will be severely affected.
4. Nightshade Family Members
All of these plants are susceptible to the same diseases, like early and late blight, and these diseases build up in the soil, getting worse each year. Planting them near each other makes the diseases worse.
Typically, you don’t want to plant anything underneath black walnut trees because their leaves and plant parts contain a compound called juglone. Juglone inhibits the growth of tomatoes and all nightshade plants.
You have many tomato companion plants to pick from when planning your garden beds. But remember to keep your tomato plants away from these five bad ones to ensure your plants stay healthy!