Choosing the ideal companion plants for tomatoes might require a bit of trial and error, considering the plant’s susceptibility to blight, fungi, and pests that share our fondness for tomatoes. However, rest assured, there exists a plethora of excellent companion plants capable of promoting healthier, more resilient tomato plants in the long run.
In this insightful piece, we’re set to reveal the finest companion plants for tomatoes and caution you against the ‘pitfall plants’ that could potentially sabotage your efforts. By the end of this read, you’ll be well-equipped to embark on your own journey of companion planting experimentation, and we’re confident you’ll be thrilled with the results.
So, if you’re eager to dive in, let’s get started on this exploration of the best (and worst) companion plants for tomatoes!
Table of Contents
The best companion plants for tomatoes
Tomatoes are a staple crop in just about every garden and as everyone knows, they really have their share of pests! Thankfully, with the right companion plants, you can help to protect them and realize many other different benefits, depending on what plants you choose to put close.
In this section, we’ll share some of the best options with you and we’ll divide them up into the following categories to keep things interesting:
- Kitchen and medicinal herbs
- Healthy Veggies and Delicious fruits
- Ornamental additions
For each plant, we’ll tell you a little about the perks, so that you can pick out one or more favorites that you can try out in your own garden. The results are sometimes nothing short of amazing, so let’s take a look and you can see what you think!
Kitchen and medicinal herbs
1. Sage
- Botanical name: Salvia officinalis
- Sun Requirements: Full sun
- Soil Type: Well-drained, loamy, sandy soil
Sage is a popular herb for the garden, with kitchen, medicinal, and even spiritual uses in some cultures, and it just-so-happens to make a great companion for your tomatoes. The trick to it is to pot the sage and then place the pots among your tomato plants.
Sage requires drier soil than tomatoes like, but if you use this little hack then the sage can attract butterflies and bees to your garden, while also repelling spider mites, flea beetles, slugs, snails, cabbage moths, and MORE. It’s a pretty good pairing, so consider giving this little ‘natural hack’ a try in your own garden – you’ll really like the results.
2. Cilantro
- Botanical name: Coriandrum sativum
- Sun Requirements: Full sun
- Soil Type: Light, well-drained soil, with organic matter
Cilantro is a cool-weather crop, but if you let it flower it can help your tomatoes by attracting pollinators and useful wasps that like to dine on hornworms! Not only that, but this useful herb will also help repel Colorado potato beetles, spider mites, aphids, and a variety of moths.
If you love having cilantro for your salsa, then consider trying this pairing on your own – after all, it doesn’t hurt to have two of your salsa ingredients together, especially will all of cilantro’s useful perks!
3. Parsley
- Botanical name: Petroselinum crispum
- Sun Requirements: Full sun, will tolerate light shade
- Soil Type: Well-drained soil, rich with organic matter, and pH 6.0-7.0 is ideal
Parsley is another useful companion plant for tomatoes, especially if you let this cool-weather crop flower. When planted with your tomatoes, the parsley will create a little groundcover that helps to keep weeds at bay, while also acting as a sort of ‘living mulch’.
The parsley also attracts ladybugs, who will happily munch on pests while beautifying your garden and benefitting both plants. As far as companion plants go, it’s a pretty good pairing that you can really get a lot of mileage out of.
4. Oregano
- Botanical name: Origanum vulgare
- Sun Requirements: Full sun (or partial shade in warmer climes)
- Soil Type: Sandy, well-drained soil
Oregano goes well with tomatoes in the kitchen, but if you’re willing to pot it then it also makes a great companion for your tomatoes. Oregano attracts a lot of useful insects, with lacewings and ladybugs being certain to find it, and the scent will also repel cabbage moths, cucumber beetles, mosquitoes, and more.
As far as the potting part, like sage, oregano needs drier soil in order to grow up healthy and strong. So, just keep it in pots and as an extra perk, you can pick another companion plant from this list and get even more benefits for your tomatoes!
5. Basil
- Botanical name: Ocimum basilicum
- Sun Requirements: Full sun
- Soil Type: Fertile, moist, and well-drained soil
Basil is an herb that we associate with tomatoes in the kitchen, but they’re also the best of friends when you plant them together in the garden. Once planted, basil starts pulling its weight by repelling pests such as whiteflies, asparagus beetles, mosquitoes, carrot flies, and tomato hornworm.
When its flowers bloom, basil will also attract pollinators and useful insects for a little added security, as well. It’s definitely a great companion planting option for your tomatoes and if the ‘old gardener tales’ are to be believed, it’s even said to improve your tomato’s yields! Try it out and see – there are definitely plenty of perks in this pairing.
Healthy Veggies and Delicious fruits
6. Celery
- Botanical name: Apium graveolens
- Sun Requirements: Full sun
- Soil Type: Loose, well-drained, organic-rich soil
Celery and tomatoes can get along quite well in your garden, and it’s also an effective way to drive off a lot of pests. Celery repels moths, cabbage worms, and a score of other pests from itself and for your nearby tomatoes, and when it blooms then it will also work in your garden’s favor.
That’s because the nectar celery produces is a big favorite of bees, who will come to have a taste and work their pollinating magic in the area to the benefit of your whole garden. It’s not a bad pairing at all, and well worth a try at home if you love celery!
7. Garlic
- Botanical name: Allium sativum
- Sun Requirements: Full sun
- Soil Type: Loamy and well-drained, with lots of organic matter
Garlic and tomatoes don’t just play well together in sauces – they’re also excellent companions. Planted close to your tomatoes, the garlic will help to keep away aphids and a whole score of other pests, who really can’t stand the scent.
What’s more, it also has antibacterial and antifungal qualities that will further protect your garlic and plants that are nearby, while also improving the soil a bit in the process. It’s a win-win, so keep this pairing in mind when you are planning your next tomato crop – you’ll be happy that you did!
8. Radishes
- Botanical name: Raphanus sativus
- Sun Requirements: Full sun
- Soil Type: Sandy, well-drained, and light soils
Radishes make excellent ‘trap plants’ and because of the way that they grow, they aren’t going to cause any problems with your tomato’s root system. This means that you can plant them close and you SHOULD, but not for harvest.
When placed close to your tomatoes, radishes will pull flea beetles in like a magnet, well before they can work their woe and defoliate your tomato crop. It’s a sacrifice on the radishes part, but it’s worth it for big ol’ tomatoes come harvest time!
9. Asparagus
- Botanical name: Asparagus officinalis
- Sun Requirements: Full sun or dappled shade
- Soil Type: Sandy, well-drained soil
Aside from tasting great with butter, Asparagus has some interesting properties that make it an excellent companion plant for your tomatoes. Starting off, these plants secrete a sort of natural fungicide that can help in keeping blight away from your tomatoes early-on.
Asparagus also releases compounds into the soil that wreak havoc for root nematodes, which helps to prevent wilt in your tomatoes quite effectively. So, if you love asparagus, consider planting it next to your tomatoes – it’ll really pull its own weight if you do!
10. Carrots
- Botanical name: Daucus carota subsp. sativus
- Sun Requirements: Full sun
- Soil Type: Sandy loam
Carrots, or more specifically, short varieties of carrot make for great companion plants for your tomatoes. These root plants will dig their way down into the soil, aerating it as they go along, so that your tomatoes will have an easier time setting up their root network.
It’s not a fancy pairing, but you’ll get healthier tomatoes and your carrots will be just fine – just be sure to use short ones, as longer carrots may not grow as well if you choose them.
11. Black-Eyed peas
- Botanical name: Vigna unguiculata
- Sun Requirements: Full sun
- Soil Type: Well-drained soil, loamy to sandy is best, 5.5-6.5 pH is optimal
If you don’t mind sacrificing part of your Black-eyed pea yield, then these plants make great companions for your tomatoes. When planted close by, the peas will add a little nitrogen to the soil, which can help to increase your tomatoes yield.
Where these peas are most useful, however, is in their desirability to southern green stink bugs – those little guys and gals just LOVE eating Black-eyed peas. You’ll lose some pods from this, but these pest-traps will keep those stink bugs busy and well away from your tomatoes. All in all, it’s not a bad trade-off and you’ll still get some beans out of it – -just nowhere near as many.
Ornamental additions
12. Lavender
- Botanical name: Lavandula
- Sun Requirements: Full sun or partial shade (if summer is very hot in your area)
- Soil Type: Fertile (low to moderate) soil, well drained, neutral to very slightly alkaline
While lavender prefers sandy soil, you can pot it and put it with your tomato crop for some definite companion planting perks. For one thing, bees LOVE the stuff, and that sweet smell will send them a’buzzin’ towards that lavender to the benefit of your whole garden.
That fragrance will also help by providing a little extra defense against flea beetles, moths, mosquitoes, and more! It’s a nice little pairing and if you’ve never smelled fresh lavender, it’s one that we highly recommend!
13. Pot Marigold
- Botanical name: Calendula officinalis
- Sun Requirements: Full sun to partial shade
- Soil Type: Well-drained soil with organic material, slightly acidic to neutral
Calendula, also known as the pot marigold, can really spice up their corner of your garden by adding orange and yellow flowers to go with your tomato crop. What’d more, these flowers that look so pretty to us, will repel quite a lot of pests from your tomatoes.
The woody fragrance of pot marigolds tends to drive away fleas beetles, corn earworms, hornworms, aphids, and even rabbits don’t seem to like it – so that’s definitely a nice bit of security if you’ve got hungry bunnies nearby. All in all, it’s a good mix of beauty and utility and a perfect partner for your tomato plants.
14. French Marigolds
- Botanical name: Tagetes patula
- Sun Requirements: Full sun
- Soil Type: Loamy, well-drained
Speaking of yellow and orange flower options, French Marigolds produce quite lovely and fluffy flowers that you can add to a salad for a bit of edible zing! Aside from looking and tasting good, however, these plants will help to repel aphids and those pesky hornworms that love your tomatoes so much.
As a final perk, French Marigolds produce a chemical in the soil that can kill root nematodes before they become a problem for your tomatoes. They might be small and pretty, but French Marigolds really pack a punch as a companion plant for tomatoes!
15. Crimson Clover
- Botanical name: Trifolium incarnatum
- Sun Requirements: Full sun
- Soil Type: Sandy loam is best, but will grow in any well-drained soil
Crimson closer is our final good companion option and these ruby-red beauties are like killing fields for pests. Planting them with your tomatoes will accomplish quite a few nice things, such as creating an environment friendly to lady beetles and pirate bugs, which like to eat a lot of pests that might go after your tomatoes.
The Crimson Clover will also spread and keep weeds at bay, while providing a sort of living mulch that your tomatoes will appreciate, and these plants are seen as a basic honey component by bees, who will pop over to help in pollination for your garden. As a final perk, these pretty plants are technically legumes, like beans or peas, and they’ll earn their keep adding nitrogen to the soil that can really increase your tomato yield. It’s a whole lot of perks for your tomatoes in a pretty red package!
Some of the WORST companion plants for tomatoes
So, we’ve explored some of the best companion plants for tomatoes, and now it’s time to take a look at some of the WORST. Each of the plants that we will list below should be kept well away from your tomatoes and we’ll tell you a little about the ‘why’ of it, so that you can avoid these companion plant pitfalls. Let’s take a peek!
1. Cabbage
While cabbages seem like they’d get along fine with tomatoes, that’s only in the safety of your kitchen. These plants, when put together in a garden patch, will fight tooth and nail for available resources, and this is a fight that the tomatoes will usually lose. As such, it’s best to put your cabbages and tomatoes in their own separate spots – it’s better for the both of them!
2. Corn
Another pairing that is excellent in the kitchen, but makes for poor companions in your garden, corn and tomatoes should NOT be grown together. It’s not so much that the plants will compete, but rather that you’ll be making both plants much more susceptible to fungal infections, as well as moths and other pests that like to eat both corn and tomatoes.
As such, keep these two apart, unless you’re planning a feast for the insects and local fungi!
3. Dill
Dill and tomatoes are not a good mix in your garden. While it will be okay when the dill is young, when it matures it can actually damage your tomatoes’ roots, which will result in stunting the plant’s growth. You’ll be much better off growing your dill or tomatoes somewhere else.
4. Fennel
Fennel is very picky about what it will share a space with. That’s because it secretes a substance that makes the soil a little better for fennel, but which can damage or even kill some other plants. If placed next to your tomatoes, at the very LEAST they will do poorly, so you’ll want to keep that fennel far away.
5. Potatoes
Potatoes are our final ‘no no’ when it comes to companion plants for your tomatoes. When you plant these two together, potatoes are going to actively fight with your tomatoes for resources, and as they are a root vegetable, they’re going to win.
They are also susceptible to many of the same pests and blight is also a problem for both plants, so putting them together will just increase the chances of both plants getting ‘sick’. You’ll be much happier if you keep these two separated!
FAQs
It’s almost time to wrap things up, but before that happens, we’ve got a few frequently asked questions that we get on the subject of companion planting with tomatoes. We’ll keep it short and sweet and with a little luck, you might just find some useful information for your own companion planting plans. Let’s take a look!
What are some of the best companion plants for tomatoes?
In a nutshell, you might want to go with any allium plants. Onions, chives, ransoms, scallions – if it’s an allium, it’s good for your tomatoes. These Sulphur-scented staples of just about every garden tend to help keep blight at bay with antifungal and antibacterial properties, and the scent from them really gets the attention of a lot of pests and they usually decide to go the other way.
It’s a tasty, if somewhat stinky defense, courtesy of wise old Mother Nature, and it WORKS, so try making an ‘Allium fence’ for your tomatoes sometime and watch what happens – it’s a pretty effective defense.
Are any companion plants poisonous to tomatoes?
Probably the most prominent ‘no-no’ for companion planting with tomatoes would be Walnut Trees. If you’ve got them on your property, then be sure to keep tomatoes away. Most walnut trees secrete a substance called Juglone, that gets into the soil and can affect the vascular tissues of your plants.
That tissue is your plant’s network for water, so anything planted nearby that can’t resist the juglone is going to turn brown or yellow and if it doesn’t die outright, you won’t really find what’s left of the plant very appetizing. Keep your tomatoes away from it and check Google before planting anything else nearby – it’s really THAT dangerous for other plants.
Can I grow brassicas as companions for my tomatoes?
Nope, Brassicas and tomatoes will not play well together, as they are both pretty resource hungry and they’re going to fight over nutrients and water. Sadly, the tomatoes usually lose, but the best that you can expect is small, stunted brassicas and tomatoes, which you could have easily avoided by keeping them apart.
In Conclusion
In this article we’ve explored companion plants for tomatoes and there are really quite a lot of good options. Depending on what you choose, you can get defense from pests like root nematodes or hornworms, better aerated soil, predatory insects or pollinators, and more – it’s all about finding the plants you like and picking the perks.
Don’t forget some of the ‘trap plant’ options, either, like Black-eyed peas. Some gardens will have more local pests than others, and you might be surprised just how well a ‘trap plant’ companion can do as far as saving your tomatoes for a happy harvest.
We want to thank you so much for reading and we wish you the best on your companion planting adventures!
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