8 Vegetables That Work as Natural Pest Repellents While Growing in Your Garden

Strategically planting certain plants helps keep pests at bay in the vegetable garden. Strong odors and flavors, along with chemical compounds found in these vegetables, won’t annihilate pest problems on their own, but they serve as an effective component in a pesticide-free pest control strategy for better harvests.

Here are eight vegetables that deter pests.

Onions

Popular varieties of bulbing onions, green onions, spring onions, and leeks all emit a strong, sulfurous odor. Deer, rabbit, squirrels, mice and voles won’t eat onions and avoid areas where they grow. The odor masks the scent of animals’ preferred vegetables and confuses insect pests, including aphids, carrot flies, cabbage worms and loopers, spider mites, thrips, and Japanese beetles.

Onions don’t need much space and grow well as companions to cabbages, broccoli, cauliflower, kale, carrots, lettuces, tomatoes, peppers, and strawberries. Plant green and spring onions with lettuces and leafy greens. Leeks are effective when interplanted with larger crops or used as barriers.

Avoid planting onions with beans, which can stunt your bean crop.

Garlic and Shallots

Garlic and shallots also emit strong, sulfurous odors effective against a wider range of insect pests including aphids, mites, caterpillars, armyworms, moths, beetles, and whiteflies. They take up less space than bulbing onions and can be interplanted with most other vegetables, except beans, peas, asparagus, and other alliums.

Plant garlic as a perimeter “fence” around vegetable plots to keep out deer, rabbits, mice, and voles. Strong taste keeps them from eating it and, when used as a barrier, the odor turns them away.

Garlic and shallots are harvested from late June to mid July in temperate growing zones, so they are most effective when interplanted with early crops like cabbage, broccoli, cauliflower, kale, lettuce, and other leafy greens.

Mustard

Mustard greens are emerging as a biofumigant for controlling nematodes, weeds, and soilborne pathogens. This cool-weather crop serves as an excellent trap for keeping aphids, flea beetles, whiteflies, and harlequin beetles off nearby brassicas, including cabbage, broccoli, cauliflower, and Brussels sprouts.

Deer steer clear of mustard due to its strong flavor but beneficial insects, such as ichneumon wasps, are attracted to pest eggs and caterpillar larvae on the leaves.

Mustard tends to bolt when temperatures exceed 75°F, but it continues to work against weeds and soilborne pests when tilled into soil. It can be grown as a spring cover crop and works as a barrier plant to turn deer away from the vegetable garden.

Radishes

Rapid growth makes radishes ideal as companion plants and trap crops, effective for drawing flea beetles, aphids, slugs, snails, harlequin bugs, and cabbage root maggots away from tomatoes, eggplant, brassicas, cucumbers, and squash. Plenty of insect pests are actually drawn to radish leaves, which act as a decoy and draw pests away from vulnerable crops.

Plant radishes as a barrier around the perimeter of raised beds or garden plots. They can be succession sown all summer. Allow them to bolt in hot weather for flowers and seeds that attract beneficial pests to prey on other pest eggs and larvae.

Chile Peppers

Capsaicin is the chemical that makes chile peppers hot, causing skin and eye irritation on contact and a burning sensation when eaten. Squirrels, rabbits, and insect pests like caterpillar larvae, aphids, and spider mites steer clear of chile pepper plants. The flowers still attract pollinators, including bees and butterflies.

Plant chiles as a perimeter barrier around your sweet pepper plants. Whiteflies, thrips, and pepper maggot flies concentrate on the decoy plants where they can be removed.

Chiles are often used in a repellent spray on a wide variety of vegetable plants.

Asparagus

When planted as companions, asparagus and nightshade crops create a symbiotic relationship that deters insect pests from both plants. Asparagus releases a chemical toxic to root knot nematodes, a microscopic round worm that creates multiple disease and growth problems in tomatoes, eggplant, potatoes and peppers. Nightshades emit the chemical solanine—an effective repellent for asparagus beetles.

Asparagus is a perennial plant in many growing zones, so be selective about using it as a companion plant. It works best in small plots where cultivating by hand allows growing annual vegetables without disturbing perennial asparagus crowns.

Horseradish

Sulfurous compounds in horseradish repel aphids, white flies, potato beetles, and deer. It’s also considered an effective companion plant for fruit trees, since it discourages deer, rabbits, and small rodents. Its antibacterial properties control fungi that cause brown rot on fruits.

Plant horseradish as a barrier plant around the perimeter of vegetable gardens and raised beds. This perennial root can become invasive but grows well in pots, which allows you to move this repellent vegetable to the places where it’s most needed throughout the growing season.