House Grail is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

11 Companion Plants for Watermelon (with Pictures)

watermelon fruit on the ground

Watermelon is a great fruit to grow in your garden. Not only does it taste great, but it’s also really easy to grow. If you want the best from your watermelon plants, you should consider giving them some company. Companion planting is the practice of planting certain plants near each other to improve their growth and overall health.

However, not all plants make great companion plants for watermelons. But some are a match made in heaven. Consider the following options.

garden flower divider

The 11 Companion Plants for Watermelon

1. Garlic

garlic with stem
Image By: Shelley Pauls, Unsplash
Native Region: Middle Asia
USDA Growing Zone: 1 to 5
Height: 18 to 24 inches
Sun Exposure: 6 to 8 hours

Garlic is an excellent companion plant for watermelon because of its insect-repelling properties. Planting garlic next to your watermelons will help keep pests like aphids, flea beetles, and other pests at bay. What’s more, garlic’s antifungal properties will help protect your watermelon from fungus.

2. Corn

brown and green corn field
Image Credit: Michael Fischer, Pexels
Native Region: Mexico and Central America
USDA Growing Zone: 6 to 11
Height: 4 to 10 feet (most varieties)
Sun Exposure: 6 to 8 hours

Corn and watermelon make a great combination in the garden. Corn provides shade for watermelon plants, keeping them cool during hot summer days. It also helps attract beneficial insects to the garden, helping your watermelons thrive. Finally, corn naturally repels the cucumber beetles, which could harm your watermelon plants.

3. Marigolds

french marigold flower
Image Credit: yganeshbabu, Pixabay
Native Region: Tropical America, Southwestern North America, South America
USDA Growing Zone: 2 to 11
Height: 6 to 24 inches
Sun Exposure: 6 to 8 hours

Like corn, marigolds also repel cucumber beetles, but that’s not all. They also attract hoverflies, which are natural predators of aphids. The same scent that attracts hoverflies also repels squash bugs from harming your watermelon plant. The roots of the marigold plant help repel the root-knot nematode, which can reduce watermelon yield by between 20% and 30%.

4. Lettuce

green lettuce planted in soil
Image Credit: Daniel Dan, Pexels
Native Region: Mediterranean
USDA Growing Zone: 2 to 11
Height: 12 to 40 inches
Sun Exposure: 4 to 6 hours

Lettuce helps watermelon by providing a living mulch, keeping the soil cool and moist. It also adds nitrogen back into the soil, improving watermelon growth. Since the lettuce roots are very short, you don’t have to worry about them interfering with the watermelon roots.

5. Dill

garden dill with yellow flowers
Image Credit: artellliii72, Pixabay
Native Region: Asia Minor and the Mediterranean
USDA Growing Zone: 9 to 11
Height: 3 to 4 feet tall
Sun Exposure: 6 to 8 hours

Dill is a great companion plant for watermelon as it attracts beneficial insects like hoverflies, ladybugs, and parasitic wasps. These insects help control harmful pests in the garden and also aid watermelon pollination. Like lettuce, dill adds nitrogen to the soil, helping watermelons grow bigger and tastier fruits.

6. Radishes

radish crops
Image Credit: wenzlerdesign, Pixabay
Native Region: Europe and Asia
USDA Growing Zone: 2 to 11
Height: 1 to 3 feet tall
Sun Exposure: 6 to 8 hours

Radishes are fast-growing plants that can grow in tandem with watermelons without compromising the latter’s growth. Since the radishes grow so fast, they don’t have to compete for nutrients with your precious watermelon. However, they’ll give the watermelons excellent ground cover and are also a great way to mark your watermelon plants before they sprout.

7. Lavender

a field of lavender flowers
Image Credit: Natalie, Pexels
Native Region: Canary Island, North, and East Africa, South Europe, the Mediterranean, Arabia, India
USDA Growing Zone: 5 to 10
Height: 20 to 24 inches
Sun Exposure: 6 to 8 hours

Planting lavender next to your watermelons is always a good idea because it not only adds a beautiful scent to your garden but also repels insects like moths and mosquitoes. Plus, its roots release compounds that help watermelon plants resist various types of fungi.

8. Nasturtium

red orange and yellow nasturtium flowers
Image Credit: Nennieinszweidrei, Pixabay
Native Region: South and Central America
USDA Growing Zone: 9 to 11
Height: 12 to 18 inches
Sun Exposure: 6 to 8 hours

Nasturtiums attract aphids and other harmful bugs away from watermelons. They also release a chemical that helps watermelon plants resist various types of fungi. Plus, they make a beautiful and edible addition to your watermelon salads. Just be sure to remove any wilted nasturtium leaves as they can attract harmful fungi in the garden.

9. Bush Beans

green beans, also known as bush beans
Image Credit: Ed Corey, Shutterstock
Native Region: The Americas
USDA Growing Zone: 3 to 10
Height: 1 to 6 feet tall
Sun Exposure: 6 to 8 hours

Planting bush beans next to watermelons helps by adding nitrogen back into the soil and also provides ground cover, keeping watermelon fruits from touching the ground and potentially rotting. It’s worth noting that beans don’t go well with alliums like garlic, onions, and chives. Though both make excellent watermelon companion plants, only one should be planted in close proximity at a time.

10. Mint

mint plant
Image Credit: successo images, Shutterstock
Native Region: Europe, Asia, and North America
USDA Growing Zone: 3 to 11
Height: 12 inches tall
Sun Exposure: 6 to 8 hours

Mint repels harmful pests like aphids, ants, and cabbage worms from watermelon plants. It also has a beautiful scent that adds a refreshing touch to your watermelon garden. However, be sure to plant mint in a separate container or in a contained area as its roots spread rapidly and can easily take over your watermelon patch.

11. Basil

Basil Plant
Image Credit: tookapic, Pixabay
Native Region: Asia and Africa
USDA Growing Zone: 9 to 11
Height: 12 to 36 inches
Sun Exposure: 6 to 8 hours

Basil helps watermelon plants resist various types of fungi and also attracts bees for pollination. Plus, it adds a delicious flavor when added to watermelon salads or drinks. Similar to mint, it’s best to plant basil in a separate container or contained area as its roots can spread rapidly.

garden flower divider

Worst Watermelon Companion Plants

If you have watermelon in your garden, you should absolutely avoid some plants. The following are some of them.

1. Squash and Pumpkin

orange pumpkin on the ground
Image Credit: Zen Chung, Pexels

Squash and pumpkin should be nowhere near your watermelon plants. That’s because both these plants belong to the same botanical family, Cucurbitaceae, and can easily cross-pollinate with watermelons. This could result in strange and potentially inedible watermelon hybrids.

2. Potatoes

potatoes on the ground
Image Credit: Jing, Pixabay

Similarly to squash and pumpkins, potatoes also belong to the same botanical family as watermelons and should not be planted in close proximity. Cross-pollination could result in watermelon-potato hybrids, which would be strange. What’s more, potatoes attract aphids that may infest your watermelon plants.

3. Cucumber

Image Credit: Sweetaholic, Pixabay

Cucumbers are a magnet for cucumber beetles, which may cross over to your watermelon plant. These pests can transmit a deadly watermelon virus called cucumber mosaic virus. It’s best to avoid planting watermelons and cucumbers in close proximity.

garden flower divider

Final Thoughts

These are just a few of the many companion plants that work well with watermelons. Don’t forget to do some research and experimentation to see what works best for your garden. Also, be sure to use the right fertilizers and water both plants regularly for a beautiful and thriving garden. Otherwise, we wish you happy gardening!

Featured Image Credit: dimitrisvetsikas1969, Pixabay


Related posts

OUR categories

Project ideas

Hand & power tools