While old-fashioned companion planting techniques relied more on folklore than science, modern methods of companion planting are now gaining traction, thanks to hundreds of recent and on-going studies evaluating the effectiveness of various plant partnerships. In previous articles, I’ve outlined the best companion plants for tomatoes, as well as plant partnerships to benefit zucchini. Today, I’d like to introduce a dozen of the best companion plants for peppers.
12 companion plants for peppers
In my award-winning book, Plant Partners: Science-Based Companion Planting Strategies for the Vegetable Garden (Storey Publishing, 2021), I take a deep dive into the topic and introduce dozens of companion planting strategies that are proven to improve plant health and yields by deterring pests, building soil health, limiting weeds, enhancing biological control, and more. By employing these plant partnerships in your garden, you’ll create not just a more diverse growing environment, but a more resilient one, resulting in healthier, more productive plants. Let’s take a close look at twelve of the best companion plants for peppers in terms of the benefits they provide to your pepper crop.
Pepper companion plants to deter pests
The following companion plants for peppers act to mask the presence of your pepper plants, limiting a pest’s ability to find them in your garden. Most pests find their host plant through a series of cues, including both visual and olfactory (scent) cues. These two plant partnerships work by masking the volatile chemicals (odors) released by pepper plants that allow pests to discover them and feed or lay eggs.
Onions, scallions, and garlic for green peach aphids
Green peach aphids are among the most common pests of peppers. They feed spring through fall by sucking out plant juices, causing distorted growth, leaf yellowing, and leaf curl. Green peach aphids also transmit several plant viruses to pepper plants. Interplanting peppers with members of the allium family, including chives, onions, garlic, and scallions, has been shown to deter these small insects from settling on pepper plants to feed. Plant the allium crops around and in between your pepper plants. Or plant your peppers smack in the middle of your onion crop.
Basil for thrips
Tiny, slender thrips can cause big trouble on pepper plants. Their damage causes a silver, net-like appearance on the leaves, flower buds, or fruits (shown in image above). They also spread various plant diseases. They’re so small that identifying them is a challenge. Look for dead terminal shoots, tiny specks of black excrement, early fruit drop, or the net-like distortion. To deter thrips, interplant your pepper plants with basil, which has been shown to help mask pepper (and tomato) plants from thrips. The volatile chemicals released by basil plants mask those emitted from the pepper plants, making it difficult for the thrips to discover their pepper host.
Companion plants for peppers that increase biological control
Beneficial pest-eating insects play a very valuable role in the vegetable garden. Using “good bugs” to help manage “bad bugs” is known as biological control. You don’t have to purchase beneficial insects and release them into the garden (in fact, doing so is not really a useful practice for home gardeners). Instead, it’s much better to create a garden where a healthy natural population of good bugs is encouraged. Enhancing the numbers of these good bugs is one of the easiest ways to keep pest outbreaks from occurring in the first place. Using companion plants that attract and support beneficial insects is essentially putting out the welcome mat for them. When it comes to companion plants for peppers that enhance biological control, here are a handful of great options.
Dill, fennel, cilantro, and other members of the carrot family
Flowering herbs in the carrot family are exceptional companion plants for peppers. Their umbrella-shaped clusters of tiny flowers are ideal for supporting a broad array of predators of aphids, hornworms, bud worms, and other pepper pests. Tiny, non-stinging parasitic wasps feed on the nectar of these flowers and then go on to parasitize hornworms and other pest caterpillars. Other species of parasitic wasps parasitize aphids. Predatory insects like ladybugs and lacewings also drink nectar from members of the carrot family. In addition to feasting on aphids, some species also feed on whiteflies and other pepper pests. Plant dill, fennel, and cilantro in between and around your pepper plants. Since many of these good bugs fly, you can even plant these plants around the edge of your garden and still see positive results.
Sunflowers as pepper companion plants
Good ol’ sunflowers have so much to offer the garden. They’re a must-have on the list of great companion plants for peppers. Yes, they lure in pollinators, but sunflowers also enhance biological control in two ways. First, they provide nectar and pollen to beneficial pest-eating insects. Second, even when they’re not in bloom, they produce extra floral nectar (EFN) from glands on their leaf undersides. This EFN is a sweet reward for beneficial insects in exchange for managing pests. Sunflowers start producing EFN when they’re only a few inches tall. Plant lots of sunflowers in and around your pepper patch, and you’ll have plenty of good bugs around to help keep pest numbers in check.
Sweet alyssum and its benefits to peppers
The small blooms of this low-growing annual plant feed a whole host of good bugs that help a gardener manage pepper pests. Parasitic wasps, syrphid flies, tachinid flies, ladybugs, and lacewings are all found sipping from the blooms. And when they’re not drinking nectar, some of these beneficial insects are eating pests like aphids, whiteflies, and thrips, while others are laying their eggs in pests like hornworms, bud worms, and fruit worms. Underplant your pepper plants with a carpet of sweet alyssum. In addition to enhancing biological control, it’s also beautiful.
Companion plants for peppers that act as a trap crop for pests
Trap crops are plants chosen for their attractiveness to a targeted pest. The presence of a trap crop lures the pests away from the desired crop, protecting it from damage. A trap crop is essentially a sacrificial offering to the pest. There are several companion plants for peppers that serve as excellent trap crops.
Pak choi or radish for flea beetles
Flea beetles are one of the biggest pest challenges faced by gardeners. The small, ragged holes they leave behind can weaken plant growth and lead to reduced yields. Though a full-grown pepper plant tolerates flea beetle damage, a young seedling will be stunted, which can lead to delayed or reduced yields down the line. A simple trap crop of pak choi or radishes is all that’s needed to keep flea beetle damage to a minimum on your pepper plants. Flea beetles much prefer pak choi and radishes to the leaves of peppers (and eggplants and tomatoes, too). Interplant your peppers with these easy-to-grow companion plants for peppers for the best results. Sow the pak choi or radish seeds a few weeks in advance of planting the peppers into the garden.
Hot cherry peppers for pepper maggot flies
Pepper maggot flies lay eggs on developing peppers. The maggot tunnels into the fruit and eats the tissue inside. Most of the time gardeners don’t find pepper maggots until the fruit rots prematurely on the plant or you cut into the pepper and discover the wriggly beast inside. Research in Connecticut showed that farmers who planted a trap crop of hot cherry peppers around the outside of their bell pepper fields, had a 98 to 100 percent reduction in pepper maggot damage on the bell peppers. Pepper maggot flies much prefer hot cherry peppers to other varieties, so the damage was focused on this sacrificial variety, rather than on the bell peppers. In a home garden, plant hot cherry peppers around the periphery of your pepper patch, or plant a row on the outer edge of the garden.
Nasturtiums for aphids
If aphids plague your pepper plants, consider planting a nearby companion planting of nasturtiums. A favorite of aphids, the lovely round leaves of nasturtiums are much preferred by this pest. The aphids opt to feed on the nasturtiums and leave your peppers alone. Since aphids are tiny and can’t travel very far, you’ll want these two plant partners located within a foot or two of each other. As an added bonus, having lots of aphids on your nasturtiums also means you’ll be providing a consistent food source for the many beneficial insects that feed on aphids, including ladybugs, lacewings, syrphid flies, parasitic wasps, and many others. Because the population of beneficials will be high in your garden, they will also be able to help manage any aphid outbreaks elsewhere in your veggie patch, too.
Companion plants for peppers for weed control
If your garden is large and you grow a lot of peppers, you may find yourself over-run with weeds. While mulching with straw, untreated grass clippings, or shredded leaves certainly helps limit weeds, there are also some companion plants for peppers that also serve to limit weed growth. Known as a “living mulch”, these plant partners are planted in between pepper rows or on walkways, where their presence serves to displace and outcompete weeds. Be careful, though, because if you don’t mow them down regularly as specified below, they can themselves become weedy.
White clover as a living mulch
When used as a permanent living mulch, white clover (Trifoleum repens) reduces weeds, provides nitrogen to nearby plants, and if left to bloom, helps feed beneficial bugs and pollinators, too. Plant it between rows or veggies or in pathways since it’s a perennial and will not die back in the winter. Choose a shorter variety and mow the plants down with a mower or string trimmer several times a year. One study found that when white clover was used as a living mulch between crop rows, the weed control it provided was comparable to commercial herbicide application. It would work in much the same manner if grown between raised beds. Be sure to mow it down before the flowers turn into seed heads to keep it from becoming weedy itself.
Subterranean clover as a living mulch for peppers
Subterranean clover (Trifolium subterraneum) is a winter annual cover crop that can also be used as a living mulch. It grows much like peanuts do in that pegs are formed from above-ground flowers. The pegs grow downward and into the soil where the seeds are formed. If temperatures where you live regularly dip below 15 degrees F (-9 degrees C) in the winter, subterranean clover is winter killed which keeps it from becoming weedy, as long as you mow it before the pegs are formed. In a Maryland study, a subclover living mulch controlled weeds better than conventional herbicide treatments. Mow subclover regularly throughout the growing season. This keeps it from competing with crops and prevents the pegs from developing. After the plants are winter killed, plant transplants of a new crop right through the detritus. Or, till it into the soil to add organic matter and nutrients.
Companion plants for peppers to improve the soil
Plant partnerships can also be used to help improve the soil. In some cases, the companion plants are legumes (members of the pea and bean family). These plants convert nitrogen from the air into a form that other plants can use to fuel their growth. In other cases, the companion plants are cover crops that are tilled into the soil to add organic matter and nutrients.
Cowpeas as a source of nitrogen
One of the more surprising plant partners on this list of companion plants for peppers is probably cowpeas (Vigna unguiculata). This warm-season companion plant is often used as a cover crop. But, it can also be used as a nitrogen provider to nearby plants. When grown in partnership with peppers, a California study showed that the cowpeas improved pepper production by both reducing weeds and providing nitrogen. Cowpeas are best planted in spring. Interplant them with transplants of peppers, tomatoes, or summer squash. Because they produce compounds that can inhibit the germination of seeds, don’t plant any of the partner crops from seed. Only use transplants.
Companion plants for peppers to improve pollination
Annual or perennial plants with big, wide blooms or hooded flowers are great companion plants for peppers. Though pepper flowers are self-fertile (meaning they can pollinate themselves), they need to be shaken or jostled. This releases the pollen from the anthers. The wind or even you bumping into the plant can be enough to cause pollen release. However, the presence of bumble bees further improves pollination rates. Bumble bees are especially valuable pollinators to peppers and other members of the nightshade family like tomatoes and eggplants. This is because they vibrate their flight muscles very fast in a process called buzz pollination. It’s the most effective tool for knocking that pollen loose and fertilizing pepper flowers.
Large or hooded flowers to bring in the bumble bees
To boost the number of bumble bees in your vegetable garden, plant flowers that support them. Bumble bees are big, and they need a secure landing pad. Plants with large, lobed lower petals are one good option. Hooded flowers like monkshood, lupines, snapdragons, and members of the pea and bean family, need bumble bees to pop open their flowers (most smaller bees aren’t heavy enough). Broad flowers with a heavy center, like zinnias, cone flowers, tithonia, and cosmos, are another great bet. Plant plenty of these blooms in and around your vegetable garden to enhance pepper pollination.
As you can see, there are many companion plants for peppers that lead to improved plant health and yields. Don’t be afraid to experiment with various combinations and partnerships. Keep a garden journal to record your successes and failures. To learn more about science-based companion planting methods for the vegetable garden, pick up a copy of my book, Plant Partners.
For more on successful plant partnerships and growing techniques, please visit the following articles:
- The best companion plants for tomatoes
- Companion plants for zucchini
- The best plants for bees
- Vertical gardening tips
- How to plan your vegetable garden