8 Plants You Should Never Grow Next to Your Peppers

Eggplant

Always research plant families when gardening. Peppers are a member of the nightshade family—a group that also includes eggplant. It might seem like a good idea to plant similar plant families together, but that’s not necessarily the case. "Other members of the nightshade family, such as potatoes and eggplant, have similar diseases and attract similar insects that will transfer to peppers," says Dick Zondag, master gardener, horticulturist, and owner of Jung Seed Company. 

Fennel

You might love fennel—especially roasted and served alongside chicken or fish—but even though it’s right at home on your plate, one place it shouldn’t be is planted near your peppers. According to Zondag, fennel secretes a chemical called anethole that inhibits the growth of many plants, including peppers. "They should not be planted next to each other," says Zondag.

Tomatoes

Everybody loves tomatoes in the garden, but they’re another nightshade that probably shouldn’t share close space with your peppers. This doesn’t mean that you can’t grow multiple types of nightshades in your garden—they just need enough room, according to Zondag. "If planted in a different part of the garden, they may not have as much trouble as they would have if planted together," he says.

Potatoes

Potatoes are yet another nightshade that you’ll want to keep at a distance from your peppers. But since potatoes are typically grown in long rows with trenches, you probably won’t have them in the same garden area as your peppers anyway.

Corn

Peppers thrive in full sun and need at least six hours of direct sun per day, so you’ll want to scope out a pepper planting location that isn’t going to be shaded throughout the day. "Taller vegetables planted in the garden might [include] sweet corn," says Zondag. Think ahead about what other taller garden crops might eventually shade out your peppers as the season progresses.

Pole Beans and Peas

These ambitious plants love to grow tall and climb, but vine crops, if trained on trellises, would shade the plants, says Zondag. If you plan to grow pole beans or peas on trellises, keep them a sufficient distance from your peppers so they aren’t inadvertently shaded. 

Hedges and Trees

Don’t forget about other sources of shade. "If your garden is planted near hedges or trees that shade your garden, [the peppers] should be planted where they get minimal shading," says Zondag. Watch your garden throughout the day as the sun moves, as certain areas of the garden will receive shade at different times. The shade from that lilac bush may be perfect for a lemonade in the garden, but your peppers won’t appreciate it!

Brassicas

The brassica family includes cauliflower, kale, cabbage, and broccoli, among others, and this family of plants is known to release glucosinolates into the soil, which can impact the growth of nearby plants. "This should not be a huge concern to the home gardener because to be affected; the peppers would have to be [planted] very close to the brassicas—so close that they’d be in danger of being shaded out by them," says Jennifer Rensenbrink, University of Minnesota Extension master gardener volunteer. Even still, Rensenbrink recommends keeping peppers and brassicas separate. "The main reason I wouldn’t intermix brassicas and peppers is for space and light considerations," she says.

Tips for Growing Peppers

Now that you know what not to grow next to your pepper plants, heed these tips for growing a thriving pepper crop.

Choose Beneficial Companions

In addition to knowing which companion crops to avoid, it can be helpful to know what plants do work well when grown with peppers. "The best companions for peppers are shorter flowering annuals or herbs that will help bring in pollinators, like nasturtiums, cilantro, or basil," says Rensenbrink. "Mint can be very helpful to plant near peppers, as long as it is contained."

Rotate Your Crops

"It is very important to rotate your crops to maintain healthy soil," says Rensenbrink, but notes that you can perform this annual rotation by plant family—it doesn’t have to be done at the species level. "So, if you have an area that you planted with any member of the nightshade family this year, plant something else there next year—like carrots, peas, beans, or any member of the brassica family like cabbage," says Rensenbrink. "Keep track of your garden plantings from year to year with a journal to help you remember."

Try Containers

"Another great strategy for growing peppers is to simply pluck a large container right into your garden and plant the peppers in there," says Rensenbrink. "They will automatically be taller than the other plants, and their roots will be kept nice and toasty in the container. Hot roots equal happy peppers."