Table of Contents
- 1 What is Companion Planting?
- 2 Why Grow Plants Next to Other Companion Plants?
- 3 Benefits of Companion Planting
- 4 What Are Some Good Vegetable Pairings?
- 5 What Are Some Good Vegetable and Herb Pairings?
- 6 What Are Some Good Vegetable and Flower Pairings?
- 7 FAQ
- 7.1 What should definitely not be planted together?
- 7.2 What Vegetables Are Best Planted Together?
- 7.3 Can You Companion Plant Vegetables and Plants in Hydroponics?
- 7.4 What Are the Best Soils for Companion Planting?
- 7.5 How To Water A Companion Planted Vegetable Garden?
- 7.6 When Should You Companion Plant Vegetables?
- 8 References
What is Companion Planting?
Companion planting, also known as a multi-cropping system, is growing multiple crops in the same field.
These grown crops must be in a mutual relationship with each other because the parasitic or antagonistic relationship harms one companion ensuring an unsuccessful growth of another one.
Companion planting system is also known as intercropping system.
The term “companion plants”, is applicable when it is about growing vegetables with herbs or flowers.
Scientifically, this practice brings about crop diversification in a field that can be advantageous to the overall environment.
A companion planting system is practiced in organic farming.
For instance, when farmers grow lettuce, cabbage, cauliflower, or other seasonal vegetables in their fields, they also grow a few other plants as companion plants.
These plants can effectively suppress the infestation of garden pests or the growth of weeds.
In addition, these good companion plants do not inhibit the growth of the main vegetable plants.
Why Grow Plants Next to Other Companion Plants?
Many gardeners consider companion planting an awkward idea to adopt because they believe that growing two or more plants/vegetables together may suppress the growth of another. But that is not the case.
On the contrary, if the gardeners can choose such two different species that can grow in the same piece of land mutually, they will be benefited in multiple ways.
We will briefly discuss the benefits of mixed cropping in a garden.
Benefits of Companion Planting
Companion plants often act as an excellent trap that can attract pests and later kill them.
For example, Collard plants attract diamondback moths and take them away from the main plants because Collard plants are more attractive to the pests .
Some crop species exclude allelochemicals that suppress the pest’s infestation. The phenomenon is known as allelopathy.
For example, Tagetes erecta (African marigold) releases a biochemical named thiopene that repels nematodes.
This crop, therefore, is a great companion for a few vegetables. Another allelochemical, juglone, released by black walnut, can inhibit the growth of weeds.
Thus, these plants control the insects directly or discourage the establishment of the pests, indirectly attract natural enemies, and kill the pests.
Diseases caused by fungi or viruses can be spread quickly in the monocropping system and destroy an entire field by affecting the plants.
Intercropping system can slow down the speed of spreading.
If disease or pest suppressing crops like onion and garlic is planted, diseases can be controlled easily.
However, to identify it, farmers or gardeners must understand the interactions among the plants.
One can also adopt this mixed cropping practice in his/her garden to save spaces. A popular way to save space is to plant vining crops under tall plants.
Another useful technique is to plant quick-growing crops between two main or slow-growing crops.
Biodiversity for Disease and Pest Prevention
The technique of mixed cropping increases the diversity and the population of beneficial insects that either kill the garden pests or feed their young people.
Availability of these pest-eating plants can be a great way to control the insects organically.
As a result, you do not have to face a serious disease or pest outbreak in the garden .
Balance of Nitrogen in the Soil
Legumes, beans, clover, and peas have an excellent capacity to fix nitrogen, which can enhance soil fertility and productivity.
These leguminous crops use atmospheric nitrogen and fix it in their nodules with the help of nitrogen-fixing bacteria.
Thus, they supply nitrogen to the soil, and other plants uptake nitrogen from the soil solution.
Crop protection from Weather
Certain plants can protect others by providing natural defense. For example, planting corn between peppers can be a great windbreaker.
Also, some companion plants can provide shade and protection from harsh weather.
What Are Some Good Vegetable Pairings?
We will briefly discuss the best vegetable pairings that can be grown in the same vegetable garden.
- Amaranth – They attract beneficial insects and repel different pest species from the garden.
- Asparagus – Asparagus is a great companion of tomatoes. They help each other in multiple ways.
For instance, asparagus repel the root-knot nematodes from the soil, and tomatoes release a solanine chemical that drives away asparagus beetles.
- Lettuce – You can plant lettuce between two tomato plants in a row. It can create an excellent ground cover and reduces the growth of weeds.
- Squash – Squash plants can reduce water loss with the large leaves
- Garlic – Garlic repels spider mites with a strong smell. It can be an effective insecticide for tomato plants.
- Potatoes – Potatoes and tomatoes both belong to the nightshade family. Therefore, they will be the competitors of each other and will compete for similar nutrients, and they are affected by the same blight.
- Brassica/Cabbage family – It includes vegetables like cauliflower, cabbage, broccoli, etc. These vegetables inhibit the growth of tomatoes.
- Corn – Corn and tomatoes both vie and compete heavily for the same nutrients. Further, both corn and tomatoes attracts pests such as corn earworm and the tomato hornworm – so it’s best not to plant these two vegetables together.
- Carrots – These plants grow deep inside the soil, and planting them with peppers reduces weed growth.
- Beets – Beets and peppers are common plants that are often grown together. If you grow peppers outdoors, you can grow beets with them. Both of them are efficient in controlling weeds. Also, the leaves minimize soil evaporation.
- Onions – Onions need little space to grow, and the smell can naturally deter aphids and other pests.
- Lettuce and Spinach – These two plants let the peppers enjoy the sunshine and provide solid ground cover that can minimize the evaporation rate.
- Corn – These plants are windbreakers and help the peppers to stand strong.
- Garlic – Both chives and garlic deter aphids. Therefore, it’s a great idea to plant peppers with garlic.
- Beans and peas – Both of these plants can fix nitrogen, but it can be a danger if peppers are planted too close to them
- Cabbage family – Members of the cabbage family can stunt the growth of peppers because they compete for the same nutrients.
- Corn – You can plant corn with cucumbers because corn plants can provide natural trellises. It will save your space and optimize garden efficiency.
- Root vegetables – The roots of cucumber plants are shallow. Therefore, a gardener can plant deep root vegetables like carrot or beet alongside cucumbers. In addition, radishes can effectively repel cucumber beetles.
- Bush beans – It can be a wise decision to plant bush beans beside cucumbers. Beans will fix nitrogen, which is good for the cucumbers. Also, you can use the same trellis for them, and it can save a lot of your space.
- Cabbage family – Vegetables belonging to this family are cabbage, cauliflower, broccoli, etc. These vegetables are water-thirsty. They will compete for water and may inhibit the growth of cucumbers.
- Potatoes – These plants are also called heavy-feeders, though they are rooted vegetables. If you plant them right beside the cucumbers, potatoes will compete for the same nutrients.
- Melons – Both melons and cucumbers attract similar insect pests. So, diseases can outbreak in the garden within a short period if you plant them together.
- Fennel – Fennel is known to attract beneficial insects but they can kill the vegetable plants as fennel are very competitive in nature.
Related post: How To Grow Cucumbers Using Epsom Salt
- Cabbage family – You can safely plant cauliflower, cabbage, broccoli, and other vegetables belonging to this family with potatoes. These plants have a shallow root system, while potatoes can go really deep. That’s why they will not compete for resources and water.
- Horseradish – This plant can repel dangerous Colorado potato beetles and can improve their disease-resistance capacity.
- Legumes – Peas and beans are great companions for potatoes because they can release fixed nitrogen to the soil. Similarly, potato plants repel Mexican bean beetles and ensure the healthy growth of leguminous crops.
- Tomatoes – Always avoid planting potatoes near tomato or other nightshade plants as they compete for similar nutrients. In addition, all of them can be affected by similar pests and diseases.
- Root crops – Crops like carrot and beet should not be planted alongside potatoes because they will compete for the same nutrients and space. Also, wireworms and flea beetles are common pests that can damage these crops.
- Pepper – Growing pepper plants with potatoes is also a bad choice because they compete for the same nutrients.
- Beets – This underground plant uses underground space for its growth. Lettuce plants are shallow-rooted plants. So, there will be less competition among them.
- Garlic – Garlic deters aphids, ensuring a natural defense against them. You can plant near the rows of lettuce. It is called intercropping.
- Onions – Onions drive away insect pests that can damage the healthy lettuce leaves. In addition, it will repel rabbits.
- Squash and Melons – Squash and melon plants grow slowly, while lettuce grows pretty fast. So, there will be less competition among these plants.
- Bush beans – Beans and lettuce thrive very well together. Beans fix atmospheric nitrogen to the soil, increasing the availability of nitrogen. Lettuce-onions-peas can be an excellent crop combination to grow.
- Fennel – Though these plants attract beneficial insects, it’s not recommended that you grow with other vegetable species.
- Cabbage family – certain plants of this family secrete root hormones that prevent the seeds of the lettuce plants from germinating. Also, lettuce tenderizes summer radishes.
Related post: How to Plant and Harvest Your Own Lettuce in the Garden
- Onions – Onions deter many pests of carrots, including the carrot fly and carrot rust fly.
- Radishes – Radishes allow the carrots to grow well. You can plant near the carrots because radish germinates faster and loosens the soil, ensuring better growth of carrots.
- Tomatoes – Tomato plants secrete a rooting hormone that drives away a lot of pests and insects.
- Peppermint and Tobacco – These plants can repel flea beetles. These pests can damage the carrot by feeding on them.
- Lettuce – Lettuce and carrots are great companion plants because they enjoy each other’s company. Lettuce keeps the soil cool and minimizes the evaporation rate with its board leaves.
- Potatoes – Potatoes and carrots are not good companion plants as both of them are root plants and compete for the same nutrients and space. They will face a common deficiency of phosphorus nutrients.
- Cabbage family – Spinach and vegetables belonging to the cabbage family grow well with each other as they do not compete for the same nutrients. Plant them 1-2 inches away from each other, and it will not be a problem.
- Garlic – Garlic discourages pest infestation by spreading a strong smell. These plants repel spider mites, aphids, and flea beetles that damage the vegetables.
- Tomatoes, Eggplants, and Pepper – They are called nightshade plants, and spinach enjoys their company. You can plant any of them with spinach because they do not compete for the nutrients.
- Beans and Peas – Pole beans, bush beans, and snow peas can provide nitrogen to the soil, improving other vegetables’ growth. Also, there is scientific evidence that peas can improve spinach’s root development.
- Potatoes – Potatoes are heavy consumers, and that’s why many vegetables do not like the accompaniment of potatoes.
- Fennel – Most of the plants do not like growing alongside fennel because of their competitive nature.
Related post: How Long Does It Take To Grow Your Own Spinach?
- Bush or pole beans – Pole beans are great companion plants for cabbage, broccoli, and cool-season crops. They can be planted near the cabbages as bush and pole beans can provide shade for the plants.
- Onions – Onions plants can repel many cabbage pests, including Cabbage loopers, Aphids, Cabbage worms, Cabbage moths, and Japanese beetles. You need to plant them beside cabbages to protect them from these pests.
- Peas – Peas and cabbage are great companion plants. It is better to plant peas between the rows of cabbage.
- Garlic – Garlic repels aphids, cabbage moths, and Japanese beetles. The gardener can save space if he plants garlic with cabbage plants. It is a good companion plant for cabbage
- Lettuce – Lettuce is a heavy feeder plant, and cabbage does not like the company of this species. The root hormones of cabbage can inhibit the seed germination of lettuce.
- Tomatoes – Tomatoes and cabbage plants are not good companion plants, and planting tomatoes beside cabbage can produce a terrible yield because cabbage hinders the growth of tomatoes.
What Are Some Good Vegetable and Herb Pairings?
If you are looking for herbs to plant in your kitchen or garden, we have a list of 22 perennial herbs that you can grow.
- Tomatoes – Basil can repel tomato hornworm and increase the overall yield of tomato .
- Root vegetables – Carrots, Radishes, and Beets can get benefits from these aromatic herbs.
- Peppers – Basil is an effective herb for growing peppers as basil can provide general pest protection to many vegetables.
- Tomato – Parsley are good trap crops and better companion plants for tomatoes. Parsley can lure aphids and save your tomatoes.
- Green beans – Parsley can repel bean beetles from green beans. Plant them near these vegetables to increase the yield.
- Peppers -Peppers are susceptible to aphids, corn earworms, and beetles. Parsley can deter all of these pests.
- Cabbage – Cutworms can cause significant damage to the cabbage. Parsley flowers can attract the beneficial insects that feed on the damaging pests.
- Carrots – Mint can deter carrot fly that can damage the roots.
- Cabbage – The strong smell of mint can repel flea beetles and cabbage moth from the cabbage family.
- Tomatoes and Eggplants – Mint is also known to repel spider mites and aphids from tomatoes and eggplants.
- Peas and Beans – Mint can also repel rodents from peas or beans in the garden.
- Beans – These herbs secret an earthy aroma that deters Mexican bean beetles.
- Carrots -Carrot flies are the biggest problems, and Rosemary attracts these flies saving the carrots.
- Brassica -Rosemary is a good companion plant for brassica (broccoli, kale, brussels sprouts, cabbage), and both of them can benefit from each other.
- Cauliflower – Rosemary can prevent moths from damaging the leaves.
- Tomatoes – Thyme can drive away the hornworms. These worms are one of the most dangerous pests. Thyme can also enhance the taste of ripe tomatoes.
- Eggplants – Thyme can repel garden moths from eggplants organically.
- Potatoes – Thyme can protect against Colorado potato beetles.
- Cabbage – You can plant near the broccoli, Brussels sprouts, cauliflower, kohlrabi to attract the pests that can damage these crops. Thyme can provide the best resistance against the cabbage worm .
- Carrots – Carrots and chives can be grown together because chives can assist the carrots to grow bigger and better.
- Tomato – Chives can deter aphids that feed on tomatoes.
- Lettuce – Chives repel the common pests of lettuce and help these plants to produce a greater yield.
- Cucumber – Chives drive away cucumber beetles that can really make a mess.
- Brassica – Dill herbs can improve the overall health of different Brassica plants, like broccoli, cauliflower, kohlrabi, kale, etc. The herbs repel pests like cabbage looper, moth, worm, etc.
- Cucumber – Dill deters cucumber pests by attracting beneficial insects.
- Tomatoes – Dill attracts tomato hornworm that damages these plants and diminishes their growth.
Cilantro (Italian Parsley)
- Leafy vegetables -Cilantro’s flower attracts insects like hoverflies, ladybugs, lacewings, and parasitoid wasps. These insects prey on damaging pests. Plan near the leafy vegetables to kill common pests that attack cabbage, lettuce, kohlrabi, kale, and spinach.
- Legumes – Green beans and peas can be grown with cilantro because both are benefited from each other by supplying nutrients.
- Potatoes – The attracted insects also prey on potato beetles and protect the potatoes from them. Keep both of them as neighboring plants.
What Are Some Good Vegetable and Flower Pairings?
Borage flower plants attract pollinators and some beneficial insects that prey on common vegetable pests like beetles, moths, worms, and aphids. Borage grows best with certain vegetables and fruits so plant near:
You can plant near a lot of vegetables because nasturtium deters aphids, squash beetles, pests of the cabbage family, flying pests, and so on. Nasturtium are common companion plants and you can plant near:
Plant marigolds to deter beetles and nematodes. These flowers can provide a general pest protection to most of the vegetables. Both French and Mexican marigolds are better as companion plants. Marigolds grow well with:
- tomatoes and
Calendula is considered a trap crop because it attracts pests. It draws the attention of aphids, whiteflies, thrips, and other harmful pests, and confuses them with the host plants. It grows best with a wide range of vegetables, so plant near:
Chamomile’s strong aroma attracts the common cabbage pests. Also, due to their antimicrobial properties, you can plant them near fruit trees. Best companion plants to plant near chamomile are:
Sunflowers offer shade and a great space for vine plants. They also attract pollinating insects that are beneficial to any garden. You can grow sunflowers with certain plants like:
Tansy is known as a great insect repellent because it deters squash bugs, Japanese beetles, mice ants, moths, and cucumber beetles. However, be careful as these flowers are toxic to livestock. You can plant tansy plants near:
What should definitely not be planted together?
Identify the plants that compete with each other. For example, potatoes and carrots do not grow well as they are both root plants.
What Vegetables Are Best Planted Together?
It depends on the characteristics, nutrient requirements, competitive nature, and pests of the plant or vegetable you plan to grow.
For instance, thyme and nasturtium improve the growth of tomatoes.
Can You Companion Plant Vegetables and Plants in Hydroponics?
Companion planting in a hydroponics system is not required because hydroponics is an indoor and closed system.
You do not have to worry about certain pests like the ones in your backyard garden.
What Are the Best Soils for Companion Planting?
Most vegetables prefer loam soil that contains an equal proportion of sand, silt, and clay.
Also, garden soil should be well-drained because the stagnant condition can damage the root system.
For companion planting, you need to add organic materials and compost to the soil as these materials enhance soil moisture retention capacity and aeration condition.
How To Water A Companion Planted Vegetable Garden?
When you grow different varieties of vegetables and crops together in the same piece of land, you must focus on their water demands.
Lack of water is responsible for yield reduction in companion planting.
Deep-rooted vegetables should be planted together because it will ensure water availability to all the plants. If you have deep-rooted vegetables, water the garden deeply.
On the other hand, if you have shallow-rooted vegetables, you should choose shallow-rooted companion plants as well.
When Should You Companion Plant Vegetables?
You need to be aware of the season for companion planting. A companion planting guide will help you find the best companion plants to grow together.
For example, if you want to grow tomatoes, then plant the vegetables or herbs that can grow happily with tomatoes that should match the tomato growing season.
References Mitchell, E.R., Hu,G., & Johanowicz, D. (2000). Management of Diamondback Moth (Lepidoptera: Plutellidae) in Cabbage Using Collard as a Trap Crop. HortTechnology, 11(1): 150-151  Walliser, J. 2020. Plant Partners: Seven Benefits of Companion Planting. In: Gardening  Riesselman, L.B. 2011. Pest Damage Effects: Evaluating the Benefits of Perimeter Trap Cropping and Row Intercropping. Iowa State Research Farm Progress Reports. 165
Lindsey Hyland grew up in Arizona where she studied at the University of Arizona’s Controlled Environment Agriculture Center. She continued her gardening education by working on organic farms in both rural and urban settings. She started UrbanOrganicYield.com to share gardening tips and tactics. She’s happy to talk about succulents and houseplants or vegetables and herbs – or just about anything in a backyard garden or hydroponics garden.