20 Perfect Companion Plants to Grow With Watermelons

Watermelons are giant, juicy, and delicious. They’re a staple for many gardeners and a favorite summer treat. But what about all those vines?

If you have limited space, you might not want to dedicate half your garden to plants that will only produce 2-4 fruits each! Fortunately, you can make the most of your space with watermelon companion plants.

Companion planting is an easy way to make your garden work double overtime while you sit back and relax. Choose your plants wisely, and you’ll see happy plants that grow stronger and bigger because of their neighbors!

But, again—what about those vines? Surprisingly, you can companion plant with watermelons despite how much space they take up and no matter what watermelon variety you’ve decided to grow. Let me show you how a little planning will make your plants go a long way.

About Companion Planting

Companion planting isn’t a new thing; it’s been around for centuries, if not millennia. It’s the practice of putting plants that benefit each other together in the same area so they can reap the benefits. While growing one type of plant in one area may be easier for you (this is called monoculture), it doesn’t benefit the ecosystem much.

If you plant watermelons by themselves, you’ll have plenty of space for watermelons to grow. But, if you plant watermelons with nasturtiums and beans, you can have fewer aphids attacking your melons, and your melons will grow more vigorously thanks to the nitrogen-giving legumes.

The watermelons aren’t the only thing reaping benefits, though; they act as a ground cover for the beans and flowers to keep them protected.

Companion planting is part of the practice called permaculture, which, put simply, is letting nature do its thing!

Watermelons as Companion Plants

Before you choose companion plants for your watermelons, you should probably understand how watermelons behave around others. They have good traits and bad traits, so they’re not a good neighbor towards everything.

Benefits

Watermelons can keep weeds down to a minimum by choking out unwanted plants. They’re really only helpful once they have long vines, so weeds could be a problem when the plants are young. Still, you won’t have to spend as much time weeding in the summer!

The long vines can also prevent wind blowing away all your soil. If your garden isn’t protected from the wind, watermelons can help you out. The vines and roots can also prevent water from washing away soil, so the melons can help with damage control if you have torrential rain.

Disadvantages

Do you know how I said they could choke out unwanted plants? Well, they can choke out desired plants, too. While intercropping is possible, you must be strategic and ensure the vines don’t get out of control. Companion planting may look like plants along the borders or in containers if your melons are a little rowdy.

Watermelons are thirsty and hungry. You’ll need to water them a lot (they’re watermelons, after all!) and give them some extra fertilizer or compost here and there. Plants that don’t like frequent feedings won’t work well in the melon patch, so you’ll have to consider that.

Companion Plants for Watermelons

There are plenty of watermelon companion plants to choose from. Here are some of the best choices. Remember, a good neighbor to watermelons won’t compete with root space and nutrients or shade out the plant.

Basil

Basil is a friend to many in the garden. Its strong scent keeps away many pests, including thrips, which can try to make their home on your watermelon plants. Plant basil between watermelon rows or on the borders of your patch to throw insects off the scent.

Basil has a shallow root system and can have a bushy growth habit. It shouldn’t negatively affect your watermelons if you space them appropriately, but you can always plant them in a container nearby if you have any concerns.

Beans and Peas

Bush and pole varieties of beans and peas are no-brainer companion plants thanks to the nitrogen-fixing roots. They take nitrogen from the air and store it in their roots, which then deposit it into the soil as they decompose. When planted before watermelons, you’ll give them a nitrogen boost that will help them develop sturdy vines. And when planted next to watermelon, beans don’t compete for the soil’s nitrogen as they’re pulling it from the air!

You might think pole varieties and vines don’t mix, but it’s a longstanding relationship. The Three Sisters method of agriculture traditionally used by Native Americans placed corn, pole beans, and squash altogether, and you can use this same method with watermelons instead of squash

Corn or sunflowers act as a natural trellis for the legumes, legumes provide nitrogen, and watermelons act as a ground cover.

Cabbage

Since cabbage is so large, you won’t want it too close to your watermelons, but it’s still a good companion to keep around as a trap crop for pests. Many insects that like watermelons also enjoy a good cabbage, including flea beetles, cabbage loopers, aphids, beet armyworms, and thrips.

Plant cabbage at the ends of your watermelon rows to prevent them from getting in the way of the roots and vines. Many insects should flock to the cabbage, so you should see reduced damage on your melon plants. It’s up to you if you want to try to harvest the cabbage or let the critters have it.

You can also use any other brassica, like collard greens, kale, or broccoli.

Cilantro

Cilantro works well with watermelons because they won’t compete for space or create too much shade. You can plant it between or on the ends of watermelon rows.

This lovely-scented annual attracts beneficial insects like lacewings and ladybugs, especially when it goes to flower. These insects will eat pests like aphids and other soft-bodied insects that wreak havoc on your melon patch, so you’ll want to include this plant for sure!

Corn

Corn is a good plant to include in your watermelon patch if you’re trying the Three Sisters method I mentioned earlier. Use it as a trellis for beans or peas, so you don’t have to worry about putting up trellises yourself.

Corn and watermelons share many of the same pest problems, like thrips and aphids, so you may encounter more pest pressure if you don’t take preventative measures. This is why you’ll also want to include plants that repel these bugs and why companion planting is such a great method.

Dill

Ladybugs love dill almost as much as they love aphids, so you’ll want to plant a few of these near your watermelons. Other aphid-eating insects will flock to it, too. Watch out, aphids!

Dill won’t compete too hard for nutrients and water, and its growth habit won’t interfere with the melon vines. It works well between watermelon rows and shouldn’t grow vigorously enough to become a problem, especially if you’re constantly harvesting from it.

Dwarf Bee Balm

Bee balm is a gorgeous flower with eye-catching fluffy flowerheads. All sorts of beneficial insects will stop at this flower, so you might as well stick it all around the garden!

The dwarf variety is the best for planting with watermelons because of its compact growth habit. It will stay self-contained and won’t get too tall, so overcrowding won’t be much of a concern.

Garlic

Garlic has a pungent scent that many insects don’t like, so it’s a good plant to keep around for pest control purposes.

Unless you’re growing elephant garlic, the small bulbs should easily fit between watermelon rows. Don’t let it get too close to watermelon roots, though, or they’ll start competing for water and nutrients.

Lettuce

Lettuce is a great companion plant because it serves several purposes. Plant lettuce and watermelon seeds at the same time. The lettuce will grow quicker and act as a ground cover to prevent weeds, which will help your watermelon seedlings out.

You don’t have to worry about overcrowding because your lettuce will be ready to harvest by the time the watermelons need space.

Marigolds

Marigolds are great companions to almost everything in the garden, including watermelons. They repel several insects, including tomato hornworms, squash bugs, and mosquitoes. They also help control nematode populations in the soil and act as a trap crop for many pests, including aphids.

Marigolds have a compact growth habit that will work well in a watermelon patch. You can plant them on the borders or in between rows, and they won’t compete for space.

Mint

Mint works wonders when it comes to repelling aphids and flea beetles, but this aggressive grower needs to be contained! Keep it in a container or in a raised bed nearby, and make sure its underground runners don’t infiltrate your watermelon bed. (I thought I had my mint under control, but I was wrong!)

Keeping mint nearby is also convenient for dinner time because mint in a watermelon salad is delicious.

Nasturtium

Nasturtium is a popular trap crop, and for a good reason. It’s certainly one of my personal favorites because I love its unique leaves and bright flowers. But aside from its beauty, the plant attracts many pests, and planting it near your watermelon can keep aphids and caterpillars away from your melons.

This flower has a compact growth habit that shouldn’t get in the way of your watermelons, but it’s best to plant them in a container or on the end of rows.

Onions

Like garlic, onions are great companions that repel various pests with their strong scent. Depending on what kind of onion you grow, you can get them pretty close to your watermelons without any problems.

Green onions and chives will fit nicely between rows, but bulbing onions will need to be on the ends of rows away from watermelon roots. The large bulbs will interfere with the shallow watermelon roots, and both plants will be unhappy.

Oregano

Oregano can grow quickly and sprawl up to 18 inches wide. You may think it won’t work well with melons, but they’re actually decent companions. Watermelons have a shallow root system but grow a bit deeper than oregano roots.

So, when planted nearby, oregano takes the water it needs, and the watermelons take the rest of it, which helps the oregano not get overwatered. Pretty neat how they help each other out!

Poppies

Poppies are short plants that don’t get too bushy, so they’re good companions to watermelons because they won’t cast too much shade. They attract many pollinators, like bees and butterflies, so you’ll want them around to help your melons get pollinated.

Pair these with another recommended flower, and you’ll have a beautiful garden bed!

Radishes

You can make the most of your limited space with radishes. Plant watermelon and radish seeds at the same time, and you’ll be able to harvest the radishes before watermelons need space. Continually plant them near your watermelons to act as a trap crop for aphids.

Choose a small variety like the Early Scarlet Globe so you won’t have to worry about the root interfering with melon roots. Some radish varieties are huge and won’t make good companions.

Sage

You may notice that many herbs are good companions because of their shallow roots and pest-repelling powers, and sage is on that list of pals. It can repel flea beetles and cabbage loopers, both of which can be found bugging your watermelon plants.

Sage has water needs similar to oregano, so you can plant it close to watermelons as I described earlier. The sage will take the water it needs, and the watermelons will take the rest.

Snapdragons

Snapdragons are beautiful flowers that will grab your attention. It also grabs pollinators’ attention, so you’ll want to plant them near your melons!

These flowers can reach up to 15 inches tall and 3 feet wide, so they’re best used on the ends of watermelon rows away from the roots to prevent competition. They won’t cast too much shade, so they’re a good plant to keep around.

Sunflowers

Sunflowers are a great alternative to corn if you decide to use the Three Sisters gardening method. Sunflowers grow tall, sturdy stems that won’t have any problems holding up pole beans and peas and won’t cast too much shade on the watermelons. Ensure that your beans and sunflowers are watered at the base to reduce the risk of powdery mildew!

Many insects flock to sunflowers, so you’ll see pollinators and pest predators. They’ll also add a bright pop of color to your watermelon patch, which is a nice added bonus!

Tansy

Tansy is a beautiful flower that pollinators can’t get enough of, but it’s often overlooked by gardeners because it’s toxic and considered a noxious weed in some areas. Keep this one in a container and handle it with gloves, and you’ll be good to go!

This flower will bring bees, butterflies, parasitic wasps, and hummingbirds to your garden, meaning more plants will be pollinated, resulting in more watermelons.

Final Thoughts

Watermelons don’t have to be the only thing you grow in one area. There are so many compatible combinations to try out! Companion planting is a smart way to garden, so choose a couple of your favorite plants and watch the plant friendship flourish.