A Companion Planting Chart is a reference guide that shows which plants grow well together and which ones to keep apart. This evidence-based companion planting chart helps gardeners plan vegetable gardens, herb gardens, and flower beds for better yields, natural pest control, and healthier soil.
There are 7 main benefits of companion planting: pest deterrence, beneficial insect attraction, improved pollination, shade regulation, natural plant support, soil fertility improvement, and weed suppression. Gardeners use companion planting charts to pair vegetables with herbs and flowers that protect each other, attract pollinators, fix nitrogen in soil, and maximize garden space.
This guide covers 4 main components: vegetable companions for 20+ common crops, herb companion planting pairings, flower companions that attract beneficial insects, and plants to avoid planting together.
What Is Companion Planting?
Companion planting is the practice of growing different plants near each other for mutual benefit. Some plants offer protection by deterring pests, others enhance growth, improve flavor, or attract beneficial insects like parasitoid wasps, hoverflies, and pollinators.
This technique has roots in traditional and Indigenous gardening practices used for centuries. The Three Sisters Guild—corn, beans, and squash planted together—demonstrates how companion plants support one another: corn provides a natural structure for climbing beans, beans fix nitrogen in the soil, and squash leaves shade the ground to suppress weeds and retain moisture.
Modern research from the USDA, NIH, and Cornell Cooperative Extension confirms what gardeners have known for generations. Studies show that intercropping—planting different crops together—reduces pest outbreaks and increases yield compared to monoculture plantings.
The Benefits of Companion Planting
There are 8 main benefits of companion planting in vegetable gardening:
- Deterring pests: Intercropping confuses pests and makes it harder for them to find their target plants. Strong-smelling herbs like rosemary release compounds—camphor, cineole, and camphene—that repel common garden pests including aphids, beetles, and cabbage moths.
- Attracting beneficial insects: Plants like lovage attract parasitoid wasps that prey on aphids and beetles. Poached egg plants (Limnanthes douglasii) draw hoverflies whose larvae consume aphids on nearby lettuce.
- Attracting pollinators: Nectar-rich flowers like borage, zinnia, and calendula attract bees, butterflies, and other pollinators. Research validates "pollinator strips"—rows of plants designed to lure pollinators—as effective for improving harvest.
- Shade regulation: Tall plants provide shade for smaller ones that need protection from harsh sun. Corn shades lettuce, helping it thrive on hot days without bolting.
- Natural supports: Corn and sunflowers act as living trellises for climbing crops like pole beans, cucumbers, and peas.
- Healthier plants: Nasturtiums release natural pest-fighting chemicals through their roots that protect neighboring plants. Mustard, horseradish, cabbage, and kale release compounds that help defend nearby plants from pests.
- Improving soil fertility: Legumes like beans and peas fix nitrogen in the soil through root nodules, making this nutrient available for heavy-feeding neighbors. Deep-rooted plants pull nutrients from lower soil layers, enriching topsoil for shallow-rooted crops.
- Weed suppression: Dense plantings of complementary crops crowd out weeds, reducing competition and manual weeding. Squash leaves hug the soil to decrease evaporation and block weed growth.
The Science Behind Companion Planting
Research from agricultural institutions has replaced much of the hearsay that surrounded companion planting. An increasing body of scientifically grounded research proves that growing specific plants together reduces pests, boosts growth, and supports beneficial wildlife.
Key findings from companion planting research:
- More positive than negative associations: Nearly all plant associations are positive. Only 2-3 confirmed "bad" combinations exist (such as black walnut trees, which secrete growth inhibitors through their roots). Evidence supports "good" companions far more than "bad" ones.
- Flower power is underutilized: Many flowers serve as excellent natural insect repellents. Nasturtium is the most effective trap crop, taking the brunt of pest attacks to protect vegetables.
- Timing matters: Plants must be grown together from the start. Introducing companion plants after pest problems appear provides little benefit.
Tomatoes Love Basil: The Classic Example
Tomatoes and basil are longtime companions in both the kitchen and the garden.
- Studies show a reduction in tomato pests when basil is present. Basil's strong scent disguises tomatoes from pests—while pest populations decreased, no increase in pest predators was detected.
- Marigolds planted alongside tomatoes reduced whitefly populations in controlled studies.
- Borage attracts tiny parasitoid wasps that are natural enemies of tomato hornworm caterpillars, according to the Journal of Apicultural Science (2020). Borage also attracts bees, providing boosted pollination plus biological pest control.
Companion Planting Chart
This companion planting chart covers 20+ common vegetables with their best companions. Each pairing is rooted in real research from sources including the USDA, NIH, Iowa State University, and Cornell Cooperative Extension.
🥦 Broccoli Companions
Best companions for broccoli: Alyssum, Dill, Chinese Cabbage, Marigold, Nasturtium, Oregano, Sage, Thyme, Rosemary, Beet, Calendula, Geranium, Kale.
- Alyssum helps broccoli by attracting hoverflies—important natural predators of aphids, the main pest of broccoli. Source: USDA
- Chinese cabbage works as an effective trap crop planted alongside broccoli to attract and divert cabbage root flies. Source: NIH
- Dill contains repellent properties against broccoli pests and acts as a physical barrier to protect broccoli from pest attack.
- Sage reduces pest egg-laying of diamondback moths on intercropped broccoli.
- Thyme and nasturtium reduce cabbage looper and imported cabbageworm damage in broccoli. Source: Iowa State University
- Rosemary deters cabbage moths and other brassica pests with its strong aromatic compounds.
- Oregano has insecticidal properties that protect nearby brassicas.
- Calendula attracts beneficial insects like ladybugs that consume aphids.
- Geranium repels cabbage worms and Japanese beetles.
🥬 Cabbage Companions
Best companions for cabbage: Chamomile, Dill, Garlic, Nasturtium, Onion, Rosemary, Sage, Tansy, Thyme, Borage, Beans, Corn.
- Chamomile deters pests when intercropped with cabbage and enhances cabbage flavor.
- Dill intercropped with cabbage attracts parasitic wasps to control cabbage worms. Source: Kenny & Chapman (1988)
- Garlic repels diamondback moths that damage cabbage leaves.
- Thyme disrupts egg-laying of the diamondback moth on cabbage plants.
- Nasturtium, onion, and thyme plots show resistance toward cabbage worm and cabbage looper.
- Onions help cabbage by lowering pest pressure and boosting productivity.
- Sage, dill, chamomile, and hyssop disrupt the egg-laying behavior of the cabbageworm.
- Borage deters cabbage worms and attracts pollinating bees.
- Corn offers shade that cabbage appreciates in hot weather.
🥒 Cucumber Companions
Best companions for cucumber: Pole Beans, Corn, Dill, Nasturtiums, Oregano, Chili Pepper, Radish, Sunflowers, Tansy, Marigold.
- Beans add nitrogen to soil, aiding cucumber growth and reducing pest incidence. Bean flowers attract pollinators, and both can share support structures.
- Corn intercropped with cucumbers reduces cucumber insect pests by over 50% versus cucumbers grown alone.
- Dill repels aphids and mites that attack cucumbers and deters aphids and spider mites.
- Nasturtium is a trap plant that keeps cucumber beetles, squash bugs, whiteflies, and aphids away from cucumber.
- Hot Pepper intercropped with cucumber reduces root knot nematode (Meloidogyne incognita) attack and creates resistance to cucumber mosaic virus.
- Radishes repel cucumber beetles and flea beetles. Source: HortTechnology (2008)
- Sunflowers create a natural trellis for climbing cucumber vines, provide shade, and attract pollinators.
- Tansy (Tanacetum vulgare) repels cucumber beetles, ants, and flying insects.
🥕 Carrot Companions
Best companions for carrot: Chives, Leeks, Onions, Peas, Radishes, Rosemary, Sage, Summer Savory, Marigold.
- Onions intercropped with carrot significantly reduce carrot fly attacks and improve root yield. Source: Multiple studies
- Chives and leeks repel carrot fly through odor masking and interference.
- Marigolds reduce nematodes in soil to prevent root knot issues and crop stunting when grown and incorporated into soil the year before planting.
- Sage odor alters carrot fly behavior, potentially protecting carrots by disrupting the flies' host-finding ability.
- Summer Savory significantly reduces carrot psyllids, aphids, nematodes, and carrot fly.
- Peas fix nitrogen in the soil, helping carrots grow strong.
- Radishes loosen the soil, helping carrots establish better root systems.
🧄 Garlic Companions
Best companions for garlic: Beets, Carrots, Tomatoes, Cucumber, Peppers, Lettuce, Cabbage, Fruit Trees.
- Beets and carrots grow well near garlic without competing for nutrients or space.
- Tomatoes benefit from garlic's ability to prevent red spider mites.
- Cucumber gains protection as garlic repels aphids and cucumber beetles.
- Peppers experience reduced fungal diseases and pest pressure when planted with garlic.
- Lettuce and cabbage are protected from aphids by garlic's strong odor.
- Fruit trees benefit from garlic planted at the base—garlic repels aphids, onion flies, ermine moths, and Japanese beetles.
🍆 Eggplant Companions
Best companions for eggplant: Thyme, Spinach, Amaranth, Peppers, Beans, Marigold, Catnip.
- Thyme helps keep moths at bay that target eggplant foliage.
- Spinach grows well in the shade of taller eggplants, maximizing garden space.
- Amaranth attracts beneficial insects and confuses pests searching for eggplant.
- Peppers have similar water and nutrient needs, making them compatible neighbors that don't compete.
- Beans fix nitrogen that benefits heavy-feeding eggplants.
- Marigold deters flea beetles and aphids that commonly attack eggplant.
🌶 Peppers Companions
Best companions for peppers: Basil, Chives, Cilantro, Dill, Leeks, Onions, Oregano, Rosemary, Carrots, Tomatoes.
- Basil improves growth and flavor of peppers and has protective insecticidal qualities. Oregano provides similar benefits.
- Dill intercropping supports beneficial predators that help reduce corn borer damage on peppers.
- Leeks and chives repel aphids that commonly attack pepper plants.
- Onions emit strong odors that repel various pepper pests including aphids, thrips, and whiteflies.
- Rosemary benefits peppers by reducing aphids when planted within 0.5 meters (1.6 feet).
- Carrots occupy different soil depths and don't compete with pepper root systems.
🥔 Potatoes Companions
Best companions for potatoes: Basil, Beans, Calendula, Cilantro, Dill, Garlic, Horseradish, Onion, Peas, Tansy, Alyssum, Corn.
- Basil discourages Colorado potato beetles and attracts beneficial insects.
- Bush beans intercropped with potatoes improve both yield and soil health through nitrogen fixation.
- Calendula, tansy, and horseradish planted at the corner of a potato patch ward off Colorado potato beetles. Source: ACS
- Cilantro planted near potatoes reduces populations of Colorado potato beetle, aphids, carrot rust fly, and spider mites.
- Dill lures natural enemies of the Colorado potato beetle. Source: Rutgers University
- Garlic planted with potatoes at a 3:1 ratio provides best disease suppression (late blight) and yield gain.
- Onions reduce aphid and pest populations on potato plants.
- Corn uses subterranean space that complements potato's shallower roots, stabilizing soil and providing shade.
🌿 Spinach Companions
Best companions for spinach: Beans, Celery, Cilantro, Coreopsis, Peas, Radish, Eggplant, Oregano, Rosemary, Strawberries.
- Peas and pole beans provide natural shade for spinach and improve soil fertility through nitrogen fixation.
- Radishes planted alongside spinach optimize space, reduce pests, and improve overall yield.
- Coreopsis attracts beneficial insects including bees, butterflies, hoverflies, soldier beetles, and tachinid flies.
- Cilantro attracts hoverflies whose larvae consume aphids.
- Eggplant offers shade that prevents spinach from bolting in warm weather.
- Strawberries enjoy similar growing conditions and share space efficiently.
🎃 Squash Companions
Best companions for squash and pumpkins: Beans, Borage, Calendula, Corn, Lovage, Marigold, Nasturtium, Oregano, Radish, Tansy.
- Pole beans produce nitrogen for squash and pumpkin. Squash planted with corn and beans ("Three Sisters") disorients the adult vine borer.
- Borage flowers attract predators that eat squash pests, plus pollinators. Source: Permaculture Research Institute
- Marigold deters beetles, especially the striped cucumber beetle and squash bug.
- Nasturtium, radish, and tansy repel cucumber beetles that attack squash.
- Corn acts as a living trellis for climbing squash varieties.
- Calendula deters beetles and root nematodes.
🍅 Tomato Companions
Best companions for tomatoes: Asparagus, Basil, Beans, Borage, Calendula, Celery, Marigold, Parsley, Radish, Rosemary, Thyme, Garlic, Chives.
- Asparagus and tomatoes repel each other's pests—tomatoes release solanine to deter asparagus beetles, while asparagus secretes compounds that repel root-knot nematodes. Source: Rutgers
- Basil releases volatiles that prime the tomato's defense system, enhancing its response to wounding and pest attack. Source: NIH
- Bush Beans interplanted with tomatoes decrease disease incidence. Source: Jessica Walliser, Plant Partners
- Borage attracts parasitic wasps that attack aphids and tomato hornworms. Borage also attracts pollinators and enhances tomato growth, taste, and disease resistance when intercropped.
- Calendula repels tomato pests and attracts beneficial insects.
- Marigolds repel whiteflies when planted with tomatoes.
- Radish works as a trap crop for flea beetles that target young tomato seedlings.
- Rosemary oils repel aphids, thrips, and whiteflies—common tomato pests.
- Thyme reduces insect damage to tomatoes. Iowa State University research showed reduced egg-laying by adult armyworms when tomatoes were interplanted with thyme. Thyme also improves tomato root development, flowers, and fruit.
Companion Planting with Herbs
Herbs function as garden multitaskers. They smell amazing, attract pollinators, repel pests, and boost the flavor and health of nearby plants. Scatter herbs throughout vegetable beds rather than isolating them in a separate section.
There are 10 essential herbs for companion planting:
- Basil: Grows well with tomatoes, peppers, and lettuce. Repels flies, aphids, mosquitoes, and hornworms. Enhances tomato flavor.
- Chives: Natural repellent for aphids and carrot flies. Plant near carrots, lettuce, and strawberries.
- Cilantro: Attracts beneficial insects like hoverflies and lacewings that prey on aphids. Pairs with spinach, peas, and potatoes.
- Rosemary: Strong-scented and repels cabbage moths and beetles. Plant near broccoli, kale, carrots, and beans.
- Sage: Repels cabbage moths, carrot flies, and flea beetles. Place around cabbage, carrots, and tomatoes.
- Dill: A pollinator magnet that draws beneficial predators. Pairs with cucumbers, cabbage, lettuce, and onions.
- Thyme: Deters cabbage worms, cabbage loopers, and moths. Companion for eggplant, squash, and tomatoes.
- Oregano: Has insecticidal properties that protect vegetables. Works with peppers, squash, and tomatoes.
- Mint: Deters aphids, ants, and flea beetles. Plant mint in its own pot or bed—it spreads aggressively.
- Parsley: Attracts beneficial insects to protect and pollinate tomatoes. Interplant between tomato plants.
Companion Planting With Flowers
Flowers play a critical role in pest control, pollination, and soil health beyond their visual appeal.
There are 8 best flowers for companion planting:
- Calendula: Attracts beneficial insects like ladybugs, lacewings, and hoverflies. Plant near tomatoes, broccoli, and lettuce.
- Marigold: The most famous companion flower. Repels nematodes, aphids, and confuses beetles. Plant throughout the garden, especially near cucumbers and squash.
- Nasturtium: Acts as a sacrificial trap crop—attracts aphids, whiteflies, and squash bugs away from vegetables. Let nasturtiums ramble under cucumbers, squash, and beans.
- Borage: A bee magnet that deters tomato hornworms and adds trace minerals to soil. Plant near tomatoes and strawberries.
- Chamomile: Improves flavor and health of many plants. Pairs with brassicas and herbs like basil and sage.
- Geranium: Attracts Japanese beetles and releases toxins that paralyze them, reducing beetle pressure on crops. Plant near brassicas and corn.
- Alyssum: Low-growing flower that attracts pollinators and beneficial insects like lacewings. Use as a bed edge around potatoes and carrots.
- Zinnia: Attracts predators that eat whiteflies and draws pollinators. Add to any vegetable bed.
Our Favorite Companion Combinations
These are the best companion planting combinations based on research and gardening practice:
- Alyssum brings in pollinators and encourages green lacewings that eat aphids.
- Basil deters moths that lay eggs for tomato hornworms and armyworms. Basil also attracts bees, improving pollination, tomato health, and flavor.
- Dill attracts ladybugs that eat aphids and spider mites.
- Calendula or cosmos nearby attracts parasitizing wasps and aphid-hungry hoverflies. Marigolds draw pest-hungry beneficial bugs.
- Borage pairs well with tomatoes, attracting pollinating bees, and enhances strawberry flavor and vigor.
- Garlic repels aphids, onion flies, ermine moths, and Japanese beetles. Plant garlic between potato rows, alongside lettuces and cabbages, and near fruit trees with alyssum.
- Mint deters aphids, ants, and flea beetles. Plant mint in its own container—it spreads aggressively.
- Nasturtiums attract hungry caterpillars away from brassicas like cabbage, broccoli, and kale, acting as a decoy. Nasturtiums also lure black flies away from fava beans.
- Parsley attracts beneficial insects to protect and pollinate tomatoes.
- Poached egg plants (a wildflower) draw hoverflies that control aphids on nearby lettuce.
- Sage repels carrot flies and reduces injury from cabbage moths around cabbage patches.
- Sunflowers pair well with cucumbers and pole beans, providing support for climbing plants and shade for crops that become sun-stressed in hot climates.
- Tansy attracts pest-eating bugs like ladybugs and predatory wasps while repelling cutworm, which attacks asparagus, beans, cabbage, carrots, celery, corn, lettuce, peas, peppers, potatoes, and tomatoes. Tansy is a perennial—plant once and it returns each year.
Plants to Avoid Planting Together
Not all plants are compatible. Some combinations stunt growth or attract shared pests. There are 6 main plant pairings to avoid:
- Tomatoes + Corn: Both attract the same pest (corn earworm), increasing pest pressure.
- Carrots + Dill: Dill stunts carrot growth when planted too close. Keep at least 2 feet (0.6 meters) apart.
- Beans + Onions or Garlic: Alliums inhibit the growth of legumes.
- Potatoes + Tomatoes: Both are nightshade family members and spread diseases like blight between each other.
- Cucumbers + Sage: Sage stunts cucumber growth.
- Fennel + Most vegetables: Fennel inhibits growth of beans, tomatoes, and most garden vegetables. Grow fennel in isolation.
Other Companion Planting Tips to Consider
Companion planting success depends on spacing, timing, and plant height management:
- Space appropriately: Avoid overcrowding plants in the name of companionship. Plants need room for air circulation and root development.
- Rotate crops yearly: Rotate companion groupings to reduce disease and pest buildup in soil.
- Use flowers generously: Calendula, nasturtiums, alyssum, and marigolds are functional powerhouses in any garden.
- Mix flowers and herbs throughout: Scatter herbs among vegetables instead of isolating them in separate beds.
- Observe and adjust: Gardens are living ecosystems. Take notes each season and adjust pairings based on your specific microclimate.
- Use vertical space: Grow climbing companions like pole beans or cucumbers on trellises to free ground space for shade-loving plants underneath.
- Interplant fast and slow growers: Combine radishes (45 days) with carrots (70-80 days) in the same row—radishes harvest before carrots need the space.
- Consider height and sunlight: Tall plants offer beneficial shade but block light for neighboring crops when placed incorrectly. Position tall plants on the north side of beds.
More Companion Gardening Tips
Height and timing create natural advantages in companion planting:
- Lettuce, radishes, and other quick-growing plants sown between hills of melons or winter squash mature and harvest before vines need the space.
- Leafy greens like spinach and Swiss chard grow well in the shadow of corn.
- Bush beans tolerate the dappled shade that corn casts. Since their roots occupy different soil levels, they don't compete for water and nutrients.
- Don't fixate on pairing every crop. Correct spacing, sun exposure, water, and good soil management are the most important influences on plant growth.
- Start small with a few marigolds and zinnia seeds—watch beneficial bugs arrive. Other beginner options include calendula, nasturtium, basil, and borage.
Video: How to Plan a Companion Planting Garden
Visual demonstrations of companion planting show how flowers deter pests, attract pollinators, and improve soil. Seeing plant interactions in action helps gardeners understand spacing and placement.
The Online Garden Planner
Use a garden planner tool with companion planting features to visualize plant combinations before planting. Select a vegetable, view compatible companions, and drag plants into your garden layout. This prevents incompatible pairings and maximizes beneficial plant relationships.
Learn More
Expand your companion planting knowledge with these resources:
- Browse our individual vegetable companion pages for detailed pairing information.
- Explore herb companion planting guides for kitchen garden combinations.
- View flower companions that attract beneficial insects and pollinators.
Beneficial Insects in the Garden
Companion planting success relies on attracting beneficial insects. There are 6 main beneficial insects that companion plants attract:
- Parasitoid wasps: Tiny wasps that lay eggs in pest caterpillars like tomato hornworms. Attracted by lovage, dill, and borage.
- Hoverflies: Adults pollinate flowers; larvae consume large numbers of aphids. Attracted by poached egg plants, alyssum, and calendula.
- Ladybugs: Both adults and larvae eat aphids, mites, and scale insects. Attracted by dill, tansy, and marigolds.
- Lacewings: Larvae are voracious aphid predators. Attracted by alyssum and coreopsis.
- Ground beetles: Nocturnal predators that eat slugs, cutworms, and other soil pests. Attracted by oregano and clover ground cover.
- Tachinid flies: Parasitize caterpillars, beetles, and squash bugs. Attracted by coreopsis, parsley, and dill.
Is The Companion Planting Guide Scientific?
Yes, modern companion planting recommendations are grounded in scientific research. Skeptics correctly note that some traditional pairings came from anecdotal evidence. Research on specific crop combinations continues, but tens of thousands of gardener observations over the past century provide valid data.
Sources for companion planting research include:
- USDA studies on intercropping and pest reduction
- NIH research on plant volatile compounds and pest deterrence
- Iowa State University studies on herb companion effects
- Cornell Cooperative Extension Three Sisters Guild documentation
- Rutgers University research on potato and tomato companions
Science provides great insights, but practical gardening observations fill gaps that controlled studies haven't addressed yet. The effects of companion planting are subtle and depend on environmental factors. Following these guidelines helps establish planting groupings—a useful starting point when laying out 50+ different crops.
Polycultures
A polyculture blends many plants together, creating unknown interactions similar to natural ecosystems. Companion planting charts address 2-3 plant interactions; polycultures produce complex relationships among many plants.
Polyculture gardening combines root crops, groundcovers, herbs, and taller plants with different root systems and above-ground heights. Some grow tall and provide shade; others hug the ground. Some harvest early; others mature late.
There are 4 benefits of polyculture gardening:
- Increased biodiversity: Multiple plant families support diverse beneficial insect and microorganism populations.
- Better garden health: Mixed plantings reduce the spread of plant-specific diseases and pests.
- Improved overall yields: While individual crop yields may vary, total garden productivity often increases.
- Natural ecosystem mimicry: Polycultures replicate natural plant communities that have evolved together.
Start experimenting by combining 10-20 plants in each bed—15 food plants and 5 beneficial plants like marigold, nasturtium, yarrow, chamomile, or bee balm. Straight monoculture rows are unnecessary. Polyculture gardening creates healthier, more resilient gardens.