11 Great Companion Plants for Sunflowers (And 3 to Avoid)

I love planting a row of sunflowers along my vegetable garden fence. Their tall stalks add another level to the garden, and their large, yellow flowers bring sunny cheer. More than visual interest, though, sunflowers provide other benefits to the garden. They attract bees and other pollinators necessary for crops like squash and cucumbers, and the University of Virginia has found that their roots can help remove toxic metals from the soil. But not all plants get along well with sunflowers. Read on to learn which are the best companion plants for sunflowers and which should be planted elsewhere.

Best Companion Plants for Sunflowers

To receive the most benefits from sunflowers, plant them alongside some of their best friends, whether vegetables, herbs, or flowers.

1. Alliums

Onions, garlic, chives, leeks, and other alliums help repel pests with their pungent odor. This makes them great partners for sunflowers, which attract beneficial insects even as the alliums deter undesirable insects. Their roots also occupy different levels of the soil, which means they won’t compete with each other for nutrients. Growing allium vegetables is easy!

2. Basil

Basil appreciates a dappled shade to protect it from the hot afternoon sun, and sunflowers are perfect for this. Plus, basil’s strong scent helps repel some pests, and the flowers attract pollinators. Plant basil, sunflowers, and tomatoes or peppers together for an excellent companion grouping. (Why tomatoes or peppers? Find out below!)

3. Crimson clover

Crimson clover is an excellent annual groundcover or cover crop. As a nitrogen fixer, it makes nitrogen more readily available for other plants, like sunflowers. Plus, its sprawling foliage prevents weed growth, and its lovely little flowers attract pollinators and other beneficial insects, making it a great complementary companion for sunflowers.

4. Corn

Corn and sunflowers make surprisingly good companions. Both being tall, they don’t compete for sunlight, and their roots don’t compete for nutrients either. Rather, sunflowers attract ladybugs and pollinators, and some claim they even improve the flavor and yield of corn.

5. Cucumbers

Last year, one of my sunflowers unintentionally became a climbing pole for some cucumbers that didn’t have a tall enough trellis – and that sunflower did a great job as a support! If you plant sunflowers as cucumber supports, you won’t have to worry about pounding in any stakes. Just give the sunflowers a couple of inches’ head start. Sunflowers also provide shade from the hot summer sun and attract beneficial insects.

Check out my guide to growing cucumbers.

6. Lettuce

Lettuce makes for an excellent edible groundcover under sunflowers. Its broad leaves prevent both weed growth and evaporation. And if you plant the sunflowers densely enough, they can provide enough cooling shade to help keep the lettuce from bolting in the summer heat.

Here’s how to grow delicious lettuce.

7. Marigolds

The poster child of companion plants, marigolds pair with sunflowers as with most plants in the garden. These shorter, bushier annuals complement the sparser, taller sunflowers beautifully. They also make a great team: while sunflowers attract beneficials, marigolds repel pests.

8. Peppers

I find pepper seeds can be difficult to germinate, so when I do seedlings to grow, I want to protect those precious little pepper plants! Luckily, sunflowers attract ladybugs and other predatory insects that feed on pepper pests, like aphids.

A sunflower and marigold border would look lovely next to a pepper patch, and the peppers would look lovely, too, with all that pest protection.

9. Pumpkins and winter squash

Pumpkins and other winter squash act as living mulch for sunflowers, and together they make a pretty autumn scene. The broad leaves on these vining squash act as a living mulch, suppressing weeds and holding moisture in the soil. In turn, sunflowers attract pollinators essential for the fruit production of squash plants.

10. Tomatoes

Like peppers, tomatoes benefit from the predatory insects that sunflowers attract. Add basil for a powerful trio, as mentioned above. In addition to repelling insect pests with its strong aroma, basil also might improve the flavor of tomatoes, according to some gardeners.

Learn about growing tomatoes.

11. Zucchini and summer squash

Like their winter squash cousins, zucchini and other summer squash need pollinators to set fruit. Sunflowers, of course, will help attract these essential insects. And while summer squash plants don’t vine, they still have large leaves that do an excellent job of preventing weeds and keeping the soil moist.

Here’s all you need to know about growing zucchini.

Worst Companion Plants for Sunflowers

While many garden plants grow well with sunflowers, benefiting from their presence and providing benefits in return, a few plants should not be planted near sunflowers.

1. Fennel

Fennel is the hermit of the vegetable garden. It prefers to grow alone, inhibiting the growth of plants that dare to grow too near. Help keep the curmudgeonly fennel – and all your other plants – happy by designating a separate area for it.

2. Hyssop

A large plant, hyssop, requires lots of space and plenty of water. If grown with sunflowers, it might compete with them for resources. While these two plants would look pretty together, locating them in different parts of the garden is best.

3. Potatoes

Sunflowers have some allelopathic properties, inhibiting the germination of potatoes and even stunting their growth. In addition, sunflowers and potatoes share susceptibility to verticillium wilt, which means the disease could easily spread from one to the other if they are planted close together.

Sunflowers provide beauty and function in the garden, especially when paired with the right friends. I hope you feel inspired to add some of these tall, sunny plants to your garden!