For Better Homegrown Tomatoes, Always Plant These 14 Things Alongside Them

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Tomatoes are a top crop in many home gardens. Whether you can them, stew them, or pop a cherry tomato in your mouth straight from the vine, these tasty treats are a kitchen staple that complement an endless array of dishes, from spaghetti to a nourishing one-pot tomato soup. 

I've been growing tomatoes for more decades than I care to admit. It's a family thing, passed down on our homestead in Vermont over generations. In addition to my hand-me-down agriculture lessons (which I also shared with my kids), I've also spent a ton of time experimenting to discover what companion crops work best together, particularly in small spaces and urban gardens. I've delved into the science behind companion crops for many reasons, beyond the heartwarming grandpa-induced nostalgia.

There are some pretty marvelous companion crops that will help your home-grown tomatoes thrive. Whether you're looking to reduce pests naturally, preserve moisture in the soil, or boost the fruit's flavor, here are 14 things to plant alongside them for better homegrown tomatoes.

There are a lot of hungry bugs that would love to munch on your carefully cultivated tomatoes, so consider putting in a few flats of alyssum close by. This terrific bedding plant is native to the Mediterranean and it provides plenty of ground cover, suppressing weeds and keeping the soil moist (but not wet) around your tomatoes' shallow roots.

Alyssum touts loads of nectar-rich flowers that make it a fantastic companion for home-grown tomatoes because these pretty white blossoms attract a variety of predator bugs, like soldier flies and ladybugs. These little garden warriors love to snack on harmful flea beetles and hornworms, which is a good thing if you want a plentiful harvest. A single hawk moth caterpillar can strip the leaves off your vines in just a few days, and they won't stop there. The unripened fruits are also at the top of their menu, and once the leaves are gone, you can kiss your harvest goodbye.

You're probably quite familiar with basil. This aromatic herb stars in some tasty dishes, like my favorite pesto, and it reportedly has some potential medicinal benefits, too. Humans have been cultivating this flavorful member of the mint family for 5,000 years, and it's another groovy option to plant alongside your homegrown tomatoes. Not only does this herb compliment tomatoes on the plate, but it also acts as a harmless bug repellent. The fragrant scent of basil also seems to confuse the hawkmoth, so they don't lay their hornworm eggs on its leaves.

Per the American Journal of Plant Sciences, there's also some scientific evidence that basil naturally boosts the fruits' flavor by improving the production of secondary metabolites like glycoalkaloids and carotenoids (compared to tomatoes grown on their own). But what does that mean for the novice gardener? More tomatoes! Basil can increase your total yield as well as the number of shoots your plant grows. It also boosts the plant's hardiness and improves the fruit's color and taste. The exact reasons behind this are still unclear, but hey, we'll take it.

If you're on the hunt for a bit of symbiosis in your garden, add some borage to your rows alongside tomatoes. As a bushy, annual herb, it touts some strikingly bright blue flowers. These blossoms are edible in their own right, but that's not why you want to sow them next to your Early Girl tomatoes. Also known as starflower, borage enjoys the same sunny climate as tomatoes and invites several helpful pollinators to your garden, especially hardworking bumblebees. With the help of these fuzzy flyers, you'll maximize your harvest by ensuring successful pollination.

Borage can even deter harmful hornworms and cabbage worms that can quickly defoliate your tomato plant. It also enriches the soil with health-promoting trace minerals, including calcium and potassium. Calcium may prevent blossom end rot while maintaining the fruit's firmness and potassium helps your tomatoes produce growth-inducing sugars that contribute to their sweetness and acidity, giving the harvested fruit a more balanced flavor profile.

Carrots are a top crop in America that exploded in popularity in the 1980s, thanks to the introduction of baby carrots. These root veggies are nearly as popular in kitchens as a nice, juicy Better Boy tomato, and they're a great option to plant alongside your home-grown vines as they attract beneficial braconid wasps. Wasps, you say? Yes, but don't worry, this variety rarely stings humans. As far as garden residents, they're a real ally, especially the girls, because they can help you get rid of those pesky hornworms by laying their eggs inside the caterpillars. Icky but great!

Carrots are great companion crops for tomatoes for other reasons too. If you're like me, watering is my love language, but I constantly run the risk of waterlogging my crops, and tomatoes don't like that at all. The tastiest tomatoes need just the right amount of water. But that's not all. If your soil is too heavy, like dirt with a high clay content, carrots go to work by loosening up the soil around the roots, improving drainage, and making it easier for these plants to grow.

Chives are another perfect culinary companion for tomatoes. They're closely related to onions and are a popular herb that's prized for its milder flavor. Chives are easy to grow and produce beautiful, edible flowers that attract welcome pollinators like bees and butterflies. What's also great about chives is that they're perennials, and they will grow back on their own year after year.

One of the best reasons to plant a few bulbs alongside your home-grown Roma tomatoes is that they deter nasty little pests like aphids, and spider mites that want to eat your harvest before you do. Once you see one aphid, prepare for an infestation, as they belly up to the tomato buffet in crowds, munching away on its leaves and stems. If you notice yellowing leaves, spider mites could be the problem. When growing chives from seed, it's best to sow them around March or April and then plant them out in the ground by May, so be sure to plan this companion plant early each year.

Ah, garlic. I couldn't live without it and it makes a fantastic option for new horticulturists, because it's so easy to grow. This fragrant bulb is in the same family as chives and onions, and its unforgettable aroma is as yummy as it is powerful. An interesting gardening fact about garlic is that it produces a type of protein called leaf agglutinin that is toxic to many chewing and sap-sucking bugs that you definitely don't want setting up shop in your garden.

Garlic is an excellent insect repellant for all kinds of creepy crawlies that love a tomato feast as much as we do. This aromatic does a formidable job of repelling everything from aphids, slugs, and caterpillars to cutworms and mites. Oh my! It accomplishes this mighty feat by disrupting the insects' ability to find food sources, ultimately leading to death. Plus, garlic prefers full sun and well-drained soil, just like its friend the tomato, so plant them together and enjoy the perks.

Intercropping your tomatoes with green beans is another sound practice for your home garden. These easily cultivated legumes are notorious nitrogen-fixers and tomatoes are heavy feeders that thrive in nitrogen-rich soil. I've probably snapped thousands of green beans over my lifetime and there's no need to sow a half-acre to reap the tomato-supporting benefit of this companion crop. The bush variety are a great addition to a raised bed or a half-barrel on your patio, like these Quarut Plant Pots, available in sets of four.

Another perk of planting green beans, especially the "bush bean" variety, alongside your vines is that they help increase air circulation, by keeping your tomatoes spaced out rather than planting them too close together. This practice reduces the chance of spreading fungal diseases, like blight, Septoria leaf spot, and Buckeye rot. If you live in a hot, dry climate, you're probably not too worried about fungi, but don't shy away from beans. While it's true that sun-loving tomatoes prefer warm conditions, they're also sensitive to temperatures above 85 degrees Fahrenheit and may drop their buds if they get overheated (or so says my son in Phoenix). That's where beans come in. They create a nice ground cover that helps shade your soil while improving water retention.

Lettuce is another kitchen staple. Whether you wrap a burger in a leaf of iceberg or chop some romaine to layer on your grilled chicken wrap, leafy greens like lettuce are the foundation of an endless array of dishes. Growing this handy ingredient alongside your tomatoes isn't hard, even when you sow it from seed, and since it's a fast-growing crop, it's pretty satisfying to gardeners who can't wait to harvest.

My youngest son (who lives in Seattle) has several tomato/lettuce pots on his sixth-floor balcony in something quite like a Self Watering Vegetable Planter Box. There's plenty of room in this planter box for a vitamin-packed Beefsteak tomato plant and a few heads of romaine — and as a bonus, all your salad fixings are growing in one handy, space-saving spot. Like the other ground cover plants, lettuce is also a great choice to reduce water evaporation and it may even slightly inhibit weed growth.

Who hasn't wandered the garden center of their local home improvement store and found themselves enraptured by rows of eye-catching marigolds? They're everywhere because they're pretty and low maintenance. These farmers' favorites have almost identical growing requirements as tomatoes. Undemanding flowers that produce golden, orange, and red blossoms, marigolds are an attractive addition to your tomato beds, plus they deliver a few welcome science-backed benefits.

Marigolds are so much more than just a pretty face. This flower's roots contain alpha-terthienyl, a naturally occurring metabolite that attacks nematodes in the soil, keeping them from grubbing on your tomato's roots. Stick a few transplants in your raised beds under full sun and they'll get down to business wiping out slugs and whiteflies by releasing chemical compounds like limonene and pyrethrin. Marigolds also have a strong scent that can deter rabbits and deer. They're a literal crop saver for my son in Michigan's Upper Peninsula, protecting his tomatoes from the area's ravenous whitetails.

Nasturtiums, which are native to South America, are some of my favorite flowers of all time. My dad still grows them alongside his house, and of course, right next to his array of heirloom tomatoes. These blooms are the total package, being both beautiful and edible, but that's not all. They're considered a trap crop, attracting tiny, leaf-eating flea beetles away from your food-bearing plants, like tomatoes, thanks to their enticing peppery scent.

Nasturtiums may also help prevent the spread of fungal diseases by luring carrier bugs, like aphids and whiteflies, away from tomatoes. Both insects produce a sugary substance called "honeydew" which has been shown to be the ideal substrate for sooty mold. While this type of fungus isn't directly harmful to your tomatoes, it can get in the way of its attempts at photosynthesis. Because nasturtiums make excellent ground cover, they may also help prevent water from back-splashing on the low-hanging tomato leaves, preventing any fungus in the soil from spreading to the fruit.

Onions go hand-in-hand with tomatoes in the pot, but that's not all. They can mask the heady aroma of the ripening fruit and its vines, making them less appealing to some pests, like our adversaries the aphid and spider mite. However, if thrips are a concern in your garden (and they should be since these little beasts transmit tomato spotted wilt virus), there's not much a little ol' onion can do to help, as they're susceptible to these tiny winged bugs too.

A volatile organic compound in onions, called dipropyl disulfide, is known to stimulate the growth of adjacent tomato plants. It improves the soil around the roots by attracting beneficial bacteria and boosting nutrient uptake. Sowing onions alongside tomatoes may even help curb the spread of deadly soil-borne diseases like Verticillium wilt, by shutting down its ability to produce spores. So next time you're wondering what to do with that bag of sprouted onions, try sticking them in the ground alongside your tomatoes!

Dried oregano is a common spice you can find at any grocery store, but as a plant, it offers gardeners tons of applications. Whether you grow it to flavor your tomato-rich Italian cuisine or you steep the leaves for a digestion-enhancing tea, one thing is certain — for better homegrown tomatoes, always plant oregano alongside them. This herb provides a welcoming habitat for predators like ladybugs and the green lacewing. These happy hunters devour some of the tomato's worst nemeses, ranging from whiteflies and aphids to cutworms that do tons of damage to the plant's stems, leaves, and roots.

If you're into herbal medicine, you probably already know the health benefits humans can reap from this strongly pungent plant. Oregano is full of antimicrobial compounds like carvacrol and thymol that are as effective for humans as it is at preventing damaging tomato diseases. Plant it to help alleviate both fungal and bacterial pathogens, like fusarium wilt and bacteria spot.

Parsley is another wonderful biennial herb to grow near tomatoes as its flowers are a magnet for beneficial insects like bees, ladybugs, hoverflies, and braconid wasps. This group of garden friends preys on a whole array of unwanteds, like aphids, caterpillars, thrips, and whiteflies. All of these crawlies want nothing more than to eat your tomato plants before you do, so grab a few transplants at your local nursery, get them in the ground, and watch them flourish.

While parsley looks a lot like cilantro, its definitely not, and even if you don't particularly like the taste of parsley, you can just grow it next to your tomatoes and let it go to seed at the end of the season. That way you can still take advantage of parsley as a companion crop in your tomato patch. Just make sure not go overboard with intercropping, since parsley doesn't like growing near onion, garlic, or carrots, even though tomatoes do.

Radishes are a permanent ingredient on my list of must-have salad toppings because they add a pretty splash of color and crunch to a bed of greens. Plus, their mildly spicy flavor isn't as overwhelming as raw onion but still delivers that zing I love. And you guessed it: They're a great choice to plant alongside your tomatoes. Radishes can help repel flea beetles. They're another lure crop that these leaping larvae prefer over munching on our coveted seedlings.

Radishes, like carrots, also help loosen the soil and improve drainage so your tomatoes don't become waterlogged. Just try not to cram too many of these cruciferous root veggies into your rows, as radishes need plenty of space to produce those plump, tasty roots. My favorite variety has to be the Cherry Belle, and you can grab a packet of heirloom, non-GMO Cherry Belle Radish Seeds for under five bucks, but don't limit yourself as there are more than a dozen varieties of radish. They're super-fast growers, too, so you can anticipate multiple harvests each year.