Want your plants to be healthier and more productive, without the need for extra fertilizers? It may seem too good to be true, but this is exactly why companion planting has been taking the organic gardening world by storm.
While it does require some extra garden planning, it won’t be long before you notice the improvements in your plants. Once you give companion planting a try, this is likely to be a technique that you will adopt for the rest of your gardening life!
What is Companion Planting?
Companion planting refers to planting at least two different crops together in order for each one to benefit the other in specific ways. So long as you do it correctly, it’s a practical way to ensure that you get the most out of each of your plants, while also cutting back on the amount of time that you spend weeding and eradicating pests.
People have been companion planting for centuries, with each generation passing on vital information about which plants grow best together. While many used to believe that this was just hearsay, science has now caught up, proving that companion planting really does have its place in both the home garden and larger farms.
Science Behind Companion Planting
Science has confirmed that companion planting brings about physical, chemical, and biological effects that help various plants to thrive.
Interplanting increases biodiversity in a garden, which not only promotes the health of each plant, but also minimizes pests.
Pest-control is enhanced even further if you follow a companion planting practice known as refugia. This basically means creating a habitat for beneficial predatory insects that will feed on nearby pests, while also increasing pollination.
However, it’s not as simple as it may initially sound…
The science also points to other factors that need to be taken into consideration when studying companion planting. Crop density, planting times, and crop ratios all come into play here, impacting how different plant combinations interact with each other.
Of course, certain pairings, such as tomatoes and basil, have been focused on more than others, simply because the research costs money. Companion planting is a concept that is most beneficial to organic gardeners, a small percentage of those in agriculture, meaning that extensive, in-depth studies are unlikely to be carried out in the near future either.
In the meantime, there is so much anecdotal evidence out there that accompanies the growing number of scientific studies. While you shouldn’t believe everything you hear, gardening offers up plenty of room for experimentation, making it worth conducting some of your own trials based on your favorite crops.
Benefits of Companion Planting:
- Pest Control: Some plants can repel pests while others attract predatory insects that eat those pests – either way, their companions win.
- Save Space in Your Garden: Planting rows of the same crop can end up wasting a lot of space. Companion planting encourages using this space for other plants too, meaning a greater yield per square foot.
- Increased Productivity: Some plants improve the vigor of others, while others attract pollinators that ensure an abundant harvest.
- Improved Flavor: Whether due to increased sugar content to make a crop sweeter or simply improving the production of flavor molecules within a plant, certain plant combinations are known to intensify the flavor of each other.
- Extra Shading: Pairing taller plants that enjoy the full sun with shorter plants that thrive in the filtered shade keeps everyone happy and healthy.
- Healthier Soil: Plant diversity means better soil structure, which is exactly what you want in order for your plants to thrive.
- Fewer Weeds: Interplanting means that there is less bare soil in your garden, giving weeds less room to grow.
Companion Planting for Vegetables
Artichoke
Pair with: Beans, brassicas, cucumbers, lettuce, peanuts, radishes, spinach, and sweetcorn.
Avoid: Potatoes and tomatoes.
Potatoes and tomatoes can interfere with the growth of artichokes. However, nitrogen-fixing plants help to enrich the soil.
Asparagus
Pair with: Basil, carrots, dill, eggplant, marigolds, nasturtiums, parsley, rhubarb, and tomatoes.
Avoid: Garlic, onions, and potatoes.
Nightshade plants help to repel the asparagus beetle, while aromatic herbs and flowers attract beneficial pollinators.
Basil
Pair with: Asparagus, beans, beets, cabbage, chamomile, eggplant, marigolds, oregano, peppers, and tomatoes.
Avoid: Rue and sage.
Tomatoes can significantly intensify the flavor of basil, while marigold and basil work together to keep pests at bay.
Beans
Pair with: Beets, brassicas, carrots, celery, cucumber, eggplant, marigolds, peas, potatoes, radishes, strawberries, squash, and sweetcorn.
Avoid: Fennel, garlic, leeks and onions.
Marigolds effectively deter the pests that can decimate beans, but both fennel and onions can stunt their growth. Sweetcorn is great for helping pole beans grow straight and tall.
Beets
Pair with: Bush beans, brassicas, lettuce, onions, and tomatoes.
Avoid: Pole beans and tomatoes.
While bush beans add nitrogen to the soil, pole beans inhibit the growth of beets.
Brassicas
Pair with: Beets, calendula, celery, chamomile, dill, geraniums, mint, nasturtiums, onions, radishes, sage, spinach, and Swiss chard.
Avoid: Eggplant, mustard, peppers, potatoes, strawberries, and tomatoes.
Calendula flowers have a sticky coating that attracts and traps brassica pests, while dill attracts wasps that feed on those pests.
Flowering herbs attract pollinators while deterring pests. Members of the nightshade family are heavy feeders that will deprive brassicas of nutrients, so should be avoided.
Carrots
Pair with: Tomatoes, leeks, chives, mint, lavender, rosemary, and sage.
Avoid: Dill, coriander, and parsnips.
Carrots revel in the filtered shade provided by tomato plants, returning the favor by aerating the soil to improve air circulation and moisture absorption of tomato roots. The other plants listed are great for deterring carrot root fly with their strong scent.
Celery
Pair with: Beans, brassicas, cosmos, daisies, lavender, leeks, marigolds, onions, snapdragons, spinach, and tomatoes.
Avoid: Asters, carrots, parsley, parsnips, sweetcorn, and turnips.
Certain flowers are great for deterring common celery pests, and taller plants can help protect young and tender celery shoots. Keep your celery away from plants that have similar nutrient requirements – you don’t want them to have to compete.
Cucumber
Pair with: Basil, beans, celery, dill, lettuce, marigolds, nasturtiums, peas, radishes, and sweetcorn.
Avoid: Aromatic herbs and potatoes.
Cucumber growth and flavor can be inhibited by certain aromatic herbs, while potatoes prevent cucumber plants from absorbing enough water. However, marigolds and nasturtiums can deter pests, such as the cucumber beetle, and sweetcorn provides a great climbing frame for vines.
Eggplant
Pair with: Basil, beans, lettuce, marigolds, peppers, tarragon, and spinach.
Avoid: Fennel.
Basil and tarragon help to boost flavor and productivity, beans improve soil condition, and marigolds deter pests. However, fennel can inhibit the growth of eggplant.
Garlic
Pair with: Beets, carrots, chamomile, dill, eggplant, fruit trees, kale, lettuce, potatoes, and spinach.
Avoid: Asparagus, beans, parsley, peas, sage, and strawberries.
Garlic works well with most plants, although the ones on the “avoid” list are known to stunt the growth of garlic bulbs.
Leek
Pair with: Apple trees, beets, cabbage, carrots, celery, lavender, onions, and spinach.
Avoid: Beans and peas.
The scent of onions and lavender confuses pests away from leeks.
Lettuce
Pair with: Beans, beets, brassicas, carrots, chives, garlic, mint, onions, peas, radishes, and sweetcorn.
Avoid: Parsley.
Aromatic plants can help to deter common pests, including aphids and slugs. Taller climbing plants provide vital shade to lettuces, while marigolds bring in the ladybugs, meaning increased aphid control.
Mint
Pair with: Beans, beets, brassicas, lettuce, peas, peppers, radishes, and tomatoes.
Avoid: None.
Mint works well with just about any plant. The only issue is how invasive it can be if allowed to run rampant among food crops, so keep it in a pot.
Radish
Pair with: Beans, carrots, chervil, cucumbers, lettuce, nasturtiums, parsnips, peas, spinach, and squash.
Avoid: Hyssop and potatoes.
Chervil improves the flavor of radishes while cucumbers are said to increase productivity.
Rosemary
Pair with: Beans, cabbage, broccoli, peppers, and sage.
Avoid: Carrots, herbs, potatoes, and pumpkins.
Unlike most other herbs, rosemary is quite picky. Broccoli is its best companion, enriching the soil to allow rosemary to thrive.
Onion
Pair with: Beets, cabbage, carrots, lettuce, mint, parsnips, tomatoes, and rosemary.
Avoid: Asparagus, beans, and peas.
Onions repel aphids and the carrot root fly, making them a great companion plant for many vegetables.
Peas
Pair with: Beans, carrots, celery, cucumber, eggplant, parsley, potatoes, radishes, spinach, strawberries, and turnips.
Avoid: Onions.
Peas work well with most plants, apart from onions, which can inhibit their growth and reduce yield.
Pepper
Pair with: Asparagus, basil, carrots, cucumbers, onions, parsley, rosemary, spinach, Swiss chard, and tomatoes.
Avoid: Beans, brassicas, and fennel.
Basil is believed to intensify the flavor of pepper while deterring common pests. Keep beans away, since vines can easily damage young fruit.
Potatoes
Pair with: Bush beans, celery, garlic, horseradish, marigolds, onions, sweetcorn, and sweet alyssum.
Avoid: Asparagus, carrots, cherry trees, cucumbers, raspberries, peppers, squash, and tomatoes.
Sweet alyssum attracts beneficial insects, marigolds repel eelworms, and horseradish improves disease resistance. Keep potatoes away from nightshades, as these can encourage certain diseases to develop, while cherry trees can make potatoes less blight-resistant.
Radish
Pair with: Beets, brassicas, carrots, cucumber, lettuce, onions, spinach, and squash.
Avoid: Hyssop.
Radishes are quick to mature and nicely break up the soil for their companions to enjoy. They also attract cucumber beetles, making them a good sacrificial plant to protect cucumbers.
Spinach
Pair with: Brassicas, eggplants, leeks, lettuce, radishes, strawberries, and tomatoes.
Avoid: Potatoes.
Spinach can be planted with most other vegetables apart from potatoes, which can negatively affect their growth.
Squash & Zucchini
Pair with: Beans, calendula, flowering herbs, marigolds, peas, radishes, salvias, sweet potatoes, and sweetcorn.
Avoid: Brassicas, potatoes, and tomatoes.
Blight affects potatoes, tomatoes, and squash, so keep them apart. Plant your squash with corn and flowering herbs instead – squash vines love climbing up corn stalks, and flowering herbs bring in the pollinators.
Sweet Potatoes
Pair with: Beets, beans, dill, oregano, parsnips, potatoes, summer savory, and thyme.
Avoid: Squash.
Aromatic herbs can help to prevent the sweet potato weevil from damaging crops, while beans can be trained to grow in between sweet potato vines. Stay away from squash – both need a lot of space and will end up having to compete with each other for water, nutrients, and light.
Sweetcorn
Pair with: Beans, cucumbers, melons, marigolds, parsnips, peas, potatoes, squash, and sunflowers.
Avoid: Tomatoes.
Not only do beans add nitrogen into the soil for sweetcorn, but corn stalks provide a great trellis for beans and other climbers to scramble over. However, keep tomatoes away, since the two growing together can attract the corn earworm.
Tomato
Pair with: Asparagus, basil, borage, carrots, celery, chives, garlic, lettuce, marigolds, mint, onions, parsley, and spinach.
Avoid: Beets, cabbage, dill, fennel, peas, and rosemary.
Basil and marigold repel pests and encourage a greater yield, while brassicas can stunt the growth of tomatoes.
Companion Planting for Fruits
Apple
Pair with: Chamomile, chives, clematis, comfrey, daffodils, dill, garlic, leeks, nasturtiums, parsnips, and pear trees.
Avoid: Cedar, eggplant, potatoes, tomatoes, and walnut.
The right companion plants repel pests and suppress weeds, allowing the apple tree to thrive. However, cedar can spread rust diseases and walnut inhibits growth.
Apricot
Pair with: Comfrey, nasturtiums, peaches, plums, and tansy.
Avoid: Nightshade plants, oats, and sage.
Comfrey fixes nitrogen into the soil, allowing apricot trees to flourish. Keep nightshade plants away – they are prone to a fungus that could destroy your apricot trees.
Blackberry
Pair with: Almond trees, bee balm, blueberries, borage, cherry trees, chives, hazelnut, hyssop, lemon balm, mint, oak trees, pear trees, roses, and thyme.
Avoid: Eggplant, peppers, potatoes, and tomatoes.
Tall herbs encourage pollinators, while deciduous trees provide moisture and a leafy mulch each year.
Blueberry
Pair with: Bay laurel, clover, dewberries, ferns, oak trees, parsley, peppers, pine trees, potatoes, radishes, raspberries, rhubarb, strawberries, thyme, tulips, yarrow, and yew.
Avoid: Tomatoes.
Pine and oak increase acidity in the soil, which blueberries need, while the lower-growing plants provide a good ground cover.
Cherry
Pair with: Calendula, chamomile, chives, comfrey, coneflower, dandelion, garlic, lupins, oregano, roses, sorrel, sweet alyssum, and violets.
Avoid: Root crops.
Cherry trees have very shallow roots compared to other fruit trees, so avoid planting anything around the tree’s drip line that may cause a disturbance to these. Coneflowers and sorrel are great choices for potassium accumulation, while violets provide phosphorus.
Citrus
Pair with: Borage, dill, impatiens, lavender, lemon balm, lobelia, marigolds, marjoram, mint, nasturtiums, oregano, pansies, peas, tansy, thyme, and yarrow.
Avoid: Root crops.
The best citrus companions deter pests while attracting beneficial predatory insects. Since you never want to disturb the shallow roots of a citrus tree, keep root crops away.
Fig
Pair with: Comfrey, marigolds, mint, rue, and strawberries.
Avoid: Rhododendrons.
Strawberries, especially alpine varieties, provide a great living mulch, while marigolds keep nematodes away. Keep figs away from rhododendrons – these produce a chemical that will stunt the growth of your fig trees.
Grape
Pair with: Beans, blackberries, elm, geraniums, hyssop, mulberry, raspberries, roses, and peas.
Avoid: Cabbage, garlic, and lettuce.
Cabbage, garlic, and lettuce release compounds that can be harmful to grapes, stunting their growth.
Passionfruit
Pair with: Beets, carrots, eggplants, lavender, leeks, lemon balm, lettuce, marigolds, nasturtiums, potatoes, spinach, strawberries, and Swiss chard.
Avoid: Cowpeas, okra, sweetcorn, and sweet potatoes.
Choosing bee-friendly plants to grow around passionfruit vines will increase pollination of fruit.
Peach
Pair with: Basil, chamomile, chives, cilantro, comfrey, dill, garlic, marigolds, nasturtiums, strawberries, tansy, tarragon, and yarrow.
Avoid: Potatoes and tomatoes.
Flowering herbs attract pollinators and deter pests, while chamomile and comfrey enrich the soil. Avoid potatoes and tomatoes to prevent blight from spreading.
Pear
Pair with: Aromatic herbs, apple trees, beans, borage, comfrey, lavender, marigolds, nasturtiums, parsnips, and peas.
Avoid: Potatoes, raspberries, and tomatoes.
Aromatic herbs repel many of the pests that commonly infest pear trees, while nitrogen-fixing plants strengthen the tree to help it better defend itself. Allow some parsnips underneath to flower – this attracts predatory insects.
Raspberry
Pair with: Chamomile, chervil, chives, garlic, grapes, leeks, nasturtiums, onions, tansy, and yarrow.
Avoid: Blackberries, eggplant, gooseberries, potatoes, and tomatoes.
Flowering herbs attract pollinators while members of the onion family keep pests away. Keep raspberries away from other fruit bushes to prevent soil-borne diseases from spreading.
Strawberry
Pair with: Borage, chives, garlic, horseradish, marigolds, onions, peas, radishes, rhubarb, sage, and spinach.
Avoid: Brassicas.
It’s believed that strawberries taste better when grown next to borage, while onions and garlic keep common pests away.
Companion Planting for Flowers
Black Eyed Susan
Pair with: Asters, cosmos, daylilies, roses, Shasta daisies, sunflowers, peonies, and phlox.
Avoid: Very large plants and trees.
Avoid planting black eyed Susan with plants that are significantly larger, as this will prevent the flowers from receiving enough light.
Daffodil
Pair with: Apple, asters, bluebells, catmint, coneflowers, crocuses, hostas, iris, muscari, peonies, roses, and tulips.
Avoid: Onions.
Look for late season bloomers that will hide dying daffodil leaves in late spring.
Daylily
Pair with: Baby’s breath, black eyed Susan, coneflower, lavender, phlox, Russian sage, and yarrow.
Avoid: Trees.
Daylilies have an extensive root system that trees can interfere with, so keep the two apart.
Lavender
Pair with: Asters, baby’s breath, basil, daylilies, marigolds, oregano, pear trees, rosemary, sage, thyme, and zinnias.
Avoid: Vegetables.
Aromatic herbs protect lavender plants from aphids and certain flies, allowing plants to grow larger. Avoid planting drought-tolerant lavender near anything that needs lots of moisture, such as vegetables, as one of the two will end up suffering.
Lupin
Pair with: Brassicas, daffodils, delphiniums, dill, geraniums, hostas, irises, lettuce, onions, peonies, roses, and strawberries.
Avoid: Nightshade plants and trees.
Lupins can sometimes be bothered by aphids, which aromatic herbs help to repel. Avoid planting lupins near trees, as this will block much-needed light.
Marigold
Pair with: Basil, broccoli, cucumbers, eggplant, kale, lettuce, potatoes, squash, and tomatoes.
Avoid: Cabbage.
Although marigolds help to repel cabbage moths and butterflies, they inhibit growth if planted around the root zone of cabbage plants.
Nasturtium
Pair with: Anything.
Avoid: Nothing.
Nasturtiums are one of the rare plants that work well with just about everything. They’re commonly used as a trap crop for vegetables – pests swarm to the foliage, ignoring the more valuable food crops nearby.
Rose
Pair with: Catmint, chives, dianthus, garlic, lavender, lilies, onions, parsley, phlox, and thyme.
Avoid: Azaleas and hibiscus.
Aromatic herbs can deter pests from roses, and their summertime flowers, intermingled with roses, present a gorgeous display. Avoid azaleas, which require opposite growing conditions, and hibiscus, which can overcrowd rose plants.
Tulip
Pair with: Asters, aquilegia, coneflowers, crocuses, daffodils, daylilies, dianthus, forget-me-nots, grape hyacinths, hellebores, hostas, sage, tickseed, and wallflowers.
Avoid: Onions.
Daylilies, hellebores, tickseed and other late-spring bloomers are perfect for taking over once tulips start to die off. This ensures that you’re not left with empty spaces in your garden, preventing weeds from emerging.
Common Pairs of Plants to Grow Together
There are countless possible plant combinations out there, but radishes and carrots are one of the most common. Radishes loosen the soil as they grow and are harvested quite quickly, giving the emerging carrots enough room to expand.
The Three Sisters is another common grouping that’s been utilized since Native American times. This consists of climbing beans that scramble up sweetcorn stalks, with squash plants below helping to maintain soil moisture and temperature.
Companion Planting Tips:
- Combining edibles with flowers not only entices pollinators to your food crops, but gives you such a visually appealing garden.
- Companion plants can be strategically planted around fruit trees to act as a living mulch.
- Don’t limit yourself to pairs – planting groups that are as diverse as possible are best for your garden
- Don’t be tempted to overcrowd your plants – this will only lead to an increase in pests and diseases. Proper plant spacing is still important, even when companion planting.
- Nasturtiums benefit all other plants, so place these throughout your garden.
- Make a plan, even if just a rough drawing, to help determine the best layout for your garden before planting.
Conclusion
Following companion planting guides is a great way to get started when first implementing this concept in your garden. However, the rest of your knowledge will need to come from trial and error.
Everything from the weather to the timing of your plantings to soil health will impact how your plants grow, meaning that companion pairings that work well in one garden may not have the same effect in another.
Experimenting with different combinations and constantly observing your plants is the way to go if you truly want to master the art and science of companion planting.
