Basil, the fragrant “king of herbs” renowned for its culinary versatility, is a powerhouse in the garden, offering more than just delicious leaves for your dishes. Renowned for its pest-repellent properties and ability to enhance the growth and flavor of neighboring plants, basil is a prime example of a beneficial companion plant.
Companion planting with basil is a time-tested, sustainable gardening practice that maximizes the potential of your garden ecosystem. By strategically interplanting basil with compatible vegetables and herbs, you can harness its natural pest control abilities, boost overall plant health, and even elevate the flavor of your harvest. This natural approach to gardening not only reduces the need for chemical pesticides but also fosters a thriving, interconnected environment where plants mutually support each other’s growth and well-being.
Best Basil companion plants
Below are your garden’s best basil companion plants for natural pest control and better harvest.
Tomatoes (Solanum lycopersicum)
Studies have shown that interplanting basil with tomatoes can significantly reduce the incidence of tomato hornworms and whiteflies. The aromatic compounds in basil, such as methyl eugenol and estragole, act as natural repellents, confusing these pests and disrupting their feeding behavior. Additionally, research published in the Journal of Agricultural and Food Chemistry suggests that basil’s presence may improve the growth and disease resistance of tomatoes due to its potential to enhance beneficial soil microbes and trigger systemic resistance in the tomato plants.
- Spacing: Plant tomatoes 24-36 inches apart, depending on the variety. Interplant basil seedlings or transplants 12 inches apart between tomato plants.
Related : Tomato Companion Plants
Peppers (Capsicum annuum):
Basil’s strong scent, rich in compounds like linalool and methyl chavicol, deters common pepper pests like aphids, spider mites, and thrips. These pests are not only detrimental to pepper plant health but can also transmit viral diseases. Companion planting with basil offers a natural and effective way to protect peppers without resorting to chemical pesticides. A study published in the Journal of Economic Entomology found that intercropping basil with peppers reduced aphid populations by up to 50%.
- Spacing: Plant peppers 18-24 inches apart, depending on the variety. Interplant basil seedlings or transplants 12 inches apart between pepper plants.
Radishes (Raphanus sativus)
While the effectiveness of basil as a “trap crop” for radishes against flea beetles and cabbage root maggots requires further research, intercropping basil with radishes can still offer benefits. Basil’s strong aroma may help deter certain pests, and its presence can attract beneficial insects that prey on common radish pests. Additionally, companion planting with basil can improve soil health and potentially enhance the growth and flavor of nearby radishes.
Studies have shown basil’s effectiveness in repelling aphids and other pests, and its potential to attract beneficial insects makes it a valuable companion plant for many vegetables, including radishes. While more research is needed to confirm its specific impact on flea beetles and cabbage root maggots, intercropping basil with radishes remains a promising practice for natural pest control and overall garden health.
- Spacing: Sow radish seeds ½-1 inch deep and 1 inch apart. Thin seedlings to 2-3 inches apart. Interplant basil seedlings or transplants 12 inches apart between radish rows.
Related : Radish Companion Plants
Carrots (Daucus carota)
Basil and carrots share a beneficial relationship in the garden. Basil’s scent deters carrot root flies, whose larvae can burrow into carrot roots and cause significant damage. Research published in Crop Protection showed that intercropping carrots with basil reduced carrot fly infestations by up to 70%. In turn, carrots’ deep roots help break up compacted soil, improving drainage and aeration, which benefits basil’s shallow root system.
- Spacing: Sow carrot seeds ½ inch deep and 1-2 inches apart. Thin seedlings to 2-4 inches apart. Interplant basil seedlings or transplants 12 inches apart between carrot rows.
Related : Carrots Companion Plants
Eggplants (Solanum melongena)
Flea beetles, a major pest of eggplants, are repelled by basil’s aromatic compounds. Interplanting basil with eggplants has been shown to reduce flea beetle populations and damage, resulting in healthier plants and potentially higher yields. A study published in the Journal of Pest Science found that basil intercropping reduced flea beetle damage on eggplants by up to 56%.
- Spacing: Plant eggplants 24-36 inches apart, depending on the variety. Interplant basil seedlings or transplants 12 inches apart between eggplant plants.
Related : Eggplant Companion Plants
Chives (Allium schoenoprasum)
The combination of chives and basil can help deter certain pests in the garden. Chives release sulfur compounds that repel aphids, Japanese beetles, and other common garden pests. Research has shown that intercropping chives with other crops can significantly reduce aphid populations. Additionally, basil can provide some shade, which may help maintain cooler soil conditions that chives prefer, although adequate sunlight is still necessary for optimal growth. This companion planting approach can contribute to a healthier garden ecosystem and potentially reduce the reliance on chemical pesticides.
- Spacing: Plant chives 4-6 inches apart in clumps or rows. Interplant basil seedlings or transplants 12 inches apart between chive clumps or rows.
Related : Chives Companion Plants
Turnips (Brassica rapa)
Some research suggests that intercropping basil with turnips might help reduce the incidence of pests like aphids and flea beetles. Basil emits aromatic compounds, such as camphor and linalool, which may repel certain insects.
- Spacing: Plant turnips 2-4 inches apart and thin to 4-6 inches. Interplant basil seedlings or transplants 12-18 inches apart between rows.
Related : Turnips Companion Plants
Nasturtiums (Tropaeolum majus)
Nasturtiums are not only visually appealing with their vibrant blooms but also offer potential benefits for basil plants. Their flowers attract beneficial insects like ladybugs and hoverflies, which prey on aphids and other common garden pests. Additionally, nasturtiums can act as a trap crop, potentially luring some pests away from basil. A study published in Biological Control found that nasturtiums interplanted with broccoli significantly reduced aphid populations, suggesting a similar effect might be possible for basil.
- Spacing: Plant nasturtium seeds or seedlings 8-12 inches apart, allowing them to sprawl or climb as needed. Interplant basil seedlings or transplants 12-18 inches apart around the nasturtiums.
Related : Nasturtiums Companion Plants
Oregano (Origanum vulgare)
The strong aroma of oregano, primarily due to compounds like carvacrol and thymol, repels a wide range of pests, including aphids, spider mites, and cabbage moths. This natural pest control mechanism can significantly reduce the risk of infestation in basil plants, leading to healthier growth and higher yields. Furthermore, oregano, like basil, attracts beneficial pollinators, contributing to overall garden biodiversity.
- Spacing: Plant oregano 12-18 inches apart. Interplant basil seedlings or transplants 12-18 inches apart.
Related : Oregano Companion Plants
Borage (Borago officinalis)
Borage offers several benefits for basil plants. Its flowers attract pollinators like bees and hoverflies, ensuring optimal pollination of basil flowers for seed production. Additionally, borage acts as a trap crop for tomato hornworms, a major pest of tomatoes that can also occasionally affect basil plants. Research has shown that interplanting borage with tomatoes can significantly reduce hornworm populations, potentially offering some indirect protection to nearby basil plants.
Related : Borage Companion Plants
Lemon balm (Melissa officinalis)
Lemon balm’s citrusy aroma, primarily due to citronellal, repels mosquitoes and flies, which can transmit diseases to basil plants. It also attracts beneficial insects like ladybugs and lacewings, which prey on aphids and other soft-bodied pests. Some gardeners also believe that lemon balm can improve the flavor of basil when grown nearby.
- Spacing: Space lemon balm plants 12-24 inches apart to allow for adequate airflow. Plant basil seedlings or transplants 12-18 inches apart around the lemon balm.
Related : Lemon Balm Companion Plants
Thyme (Thymus vulgaris)
Thyme’s pungent aroma, attributed to thymol and carvacrol, repels whiteflies, cabbage worms, and other common garden pests. Its low-growing habit provides ground cover, helping to retain soil moisture and suppress weed growth, which benefits basil. Additionally, thyme attracts beneficial insects like hoverflies, which are natural predators of aphids.
- Spacing: Plant thyme 12-18 inches apart. Interplant basil seedlings or transplants 12 inches apart around the thyme
Related : Thyme Companion Plants
Zinnias (Zinnia elegans)
Zinnias are not only beautiful but also potentially beneficial for basil. Their colorful flowers attract a wide range of pollinators, including bees and butterflies, which are essential for basil seed production. Furthermore, zinnias can act as a trap crop, potentially drawing aphids and other pests away from basil plants. A study published in Environmental Entomology found that interplanting zinnias with peppers significantly reduced aphid populations, suggesting a similar effect might be possible for basil.
- Spacing: Plant zinnia seeds or seedlings 12-18 inches apart, depending on the variety. Interplant basil seedlings or transplants 12-18 inches apart around the zinnias.
Related : Zinnias Companion Plants
Spinach (Spinacia oleracea)
Spinach and basil can be good companions in the garden, offering potential mutual benefits. Basil’s strong aroma may help deter certain pests, including aphids and possibly leaf miners, which are common spinach pests. In return, spinach acts as a living mulch, suppressing weeds and helping retain soil moisture, which is beneficial for basil during hot and dry periods.
- Spacing: Plant spinach seeds ½-1 inch deep and 2-3 inches apart. Thin seedlings to 4-6 inches apart. Interplant basil seedlings or transplants 12-18 inches apart between spinach rows.
Related : Spinach Companion Plants
Asparagus (Asparagus officinalis)
While asparagus is a perennial plant that requires more space than annuals like basil, it can still benefit from this aromatic companion. Basil’s scent repels asparagus beetles and aphids, common pests that can damage asparagus spears. In return, asparagus ferns can provide some shade for basil, protecting it from excessive heat, especially in warmer climates.
- Spacing: Plant asparagus crowns 12-18 inches apart in rows spaced 4-5 feet apart. Interplant basil seedlings or transplants 12-18 inches apart between asparagus rows, ensuring they receive adequate sunlight.
Related : Asparagus Companion Plants
Marigolds (Tagetes spp.)
Marigolds are renowned for their pest-repellent properties. They release a compound called alpha-terthienyl, which is toxic to nematodes, a common soil-dwelling pest that can damage basil roots. Additionally, marigolds attract beneficial insects like ladybugs and lacewings, which feed on aphids and other pests.
- Spacing: Plant marigold seeds or seedlings 6-12 inches apart, depending on the variety. Interplant basil seedlings or transplants 12-18 inches apart between marigold rows.
Chamomile (Matricaria chamomilla)
Chamomile is a beneficial companion for basil. Its flowers attract hoverflies and ladybugs, natural predators of aphids and other basil pests. Chamomile also has antifungal properties that can help protect basil from soil-borne diseases. Additionally, some gardeners believe that chamomile can improve the growth and flavor of neighboring plants, including basil, although this claim lacks scientific evidence.
- Spacing: Sow chamomile seeds directly in the ground, scattering them thinly and covering them lightly with soil. Thin seedlings to 6-12 inches apart. Interplant basil seedlings or transplants 12-18 inches apart between chamomile plants.
Lettuce (Lactuca sativa)
Lettuce and basil can create a microclimate that offers potential benefits to both plants. Lettuce’s growth can provide some shade for basil, helping to retain soil moisture, which is particularly important during hot weather. However, it’s crucial to ensure basil still receives enough sunlight for optimal growth. In return, basil’s strong aroma, particularly from compounds like linalool and methyl chavicol, can repel aphids, a common lettuce pest.
- Spacing: Plant lettuce 6-12 inches apart, depending on the variety, and interplant basil seedlings 12-18 inches apart between lettuce rows.
Related : Lettuce Companion Plants
Beets (Beta vulgaris)
Beets are known for their deep taproots, which can help aerate the soil and improve its drainage, potentially creating a more favorable environment for basil roots. Studies have shown that basil’s aromatic compounds can repel certain pests, including aphids and flea beetles. Additionally, the vibrant colors of beets, particularly the flowers, can attract beneficial insects like ladybugs and lacewings, which prey on common basil pests. This combination could potentially contribute to a healthier garden ecosystem and reduce pest pressure on both plants.
- Spacing: Plant beets 2-4 inches apart and thin them to 4-6 inches apart as they grow. Interplant basil seedlings 12-18 inches apart between beet rows.
Related : Beets Companion Plants
Petunias (Petunia x hybrida)
While not a vegetable, petunias offer significant benefits as a companion plant for basil. Their bright, colorful flowers attract beneficial insects like ladybugs and lacewings, which prey on aphids and other basil pests. Additionally, petunias can act as a sacrificial crop for certain pests, drawing them away from basil plants.
- Spacing: Plant petunia seeds or seedlings 8-12 inches apart, depending on the variety. Interplant basil seedlings or transplants 12-18 inches apart around the petunias
Leeks (Allium ampeloprasum)
Leeks, like other members of the Allium family, emit sulfur compounds that repel pests like onion flies and thrips. These compounds also have antifungal and antibacterial properties, potentially protecting basil from soil-borne diseases. Additionally, leeks’ deep roots help break up compacted soil, improving aeration and water infiltration, which benefits basil’s shallow root system.
- Spacing: Plant leeks 4-6 inches apart and thin them to 6-8 inches as they grow. Interplant basil seedlings 12-18 inches apart between leek rows.
Related : Leeks Companion Plants
Parsnip (Pastinaca sativa)
Parsnips and basil could potentially make good companions in the garden. Basil’s strong aroma help to repel parsnip webworms. In return, parsnips’ deep taproots help break up compacted soil, improving its structure and drainage, which benefits basil’s shallow root system.
- Spacing: Plant parsnip seeds 1/2 inch deep and 3-4 inches apart. Thin seedlings to 6-8 inches apart. Interplant basil seedlings or transplants 12-18 inches apart between parsnip rows.
Marjoram (Origanum majorana)
Marjoram and basil are closely related herbs with similar pest-repelling properties. Both plants emit aromatic compounds, including terpenes and phenols, that deter aphids, spider mites, and other common garden pests. Studies have shown that interplanting marjoram with basil can reduce pest pressure and improve the overall health and vigor of both plants.
- Spacing: Plant marjoram and basil 12-18 inches apart, either in separate rows or interplanted.
Garlic (Allium sativum)
Garlic is a powerful natural pest repellent, thanks to its sulfur-containing compounds like allicin. When planted near basil, garlic can deter aphids, spider mites, and Japanese beetles, protecting basil from damage and disease. Additionally, some gardeners believe that garlic’s pungent aroma may enhance the flavor of basil leaves, adding a subtle complexity.
- Spacing: Plant garlic cloves 4-6 inches apart and basil 12-18 inches apart, either in separate rows or interplanted.
Beans (Phaseolus vulgaris)
Beans are indeed nitrogen-fixing plants, enriching the soil with nitrogen. However, they can also cast a fair amount of shade, which may not be ideal for basil, especially in cooler climates. Furthermore, beans can attract certain pests, like spider mites and aphids, which could also affect basil.
- Spacing: Plant beans and basil with some distance between them (at least 2-3 feet) to avoid excessive shading and potential pest transfer. Consider using trellises for beans to maximize space.
Frequently Asked Questions About Basil Companion Planting
1. What are the benefits of companion planting with basil?
Companion planting with basil offers numerous benefits, including:
- Natural Pest Control: Basil’s strong aroma repels common garden pests like aphids, spider mites, and whiteflies, reducing the need for chemical pesticides. (Source: The Old Farmer’s Almanac)
- Improved Growth: Some companion plants, like carrots, help loosen soil and improve aeration, benefiting basil’s root growth.
- Enhanced Flavor: Basil can enhance the flavor of neighboring plants, particularly tomatoes and peppers. (Source: National Sustainable Agriculture Information Service)
- Increased Biodiversity: A diverse garden is a healthier garden, less susceptible to pests and diseases.
2. Can basil be planted with all vegetables?
No, basil is not compatible with all vegetables. Some plants, like fennel and rue, can inhibit basil’s growth or negatively impact its flavor. It’s essential to research compatible companions for your specific basil variety and growing conditions.
3. When is the best time to plant basil with companion plants?
Basil thrives in warm weather and is typically planted after the last frost. It’s best to plant basil seedlings or transplants alongside your chosen companion plants once the soil has warmed up and all threat of frost has passed.
4. How close should I plant basil to its companion plants?
The ideal spacing depends on the specific companion plant. Generally, basil should be planted 12-18 inches apart from most companion vegetables. For smaller plants like radishes or lettuce, basil can be interplanted between rows.
5. Can I grow basil in containers with companion plants?
Yes, you can grow basil in containers with compatible companions. Choose a container that’s large enough to accommodate both plants with sufficient space for root growth. Ensure the container has good drainage and use a high-quality potting mix.
6. Do I need to fertilize basil and its companion plants?
Basil is a light feeder and doesn’t require heavy fertilization. A balanced organic fertilizer applied once a month should be sufficient. However, the fertilization needs of companion plants may vary, so it’s important to research their specific requirements.
7. Can companion planting with basil completely eliminate the need for pest control?
While companion planting with basil can significantly reduce pest pressure, it may not completely eliminate the need for pest control in all cases. Regular monitoring and early intervention are still crucial for maintaining a healthy garden.
Conclusion
Companion planting with basil is a testament to the interconnectedness of nature and the power of biodiversity in the garden. By strategically pairing basil with compatible plants, we can create a thriving ecosystem that naturally deters pests, enhances plant health, and improves yields. The evidence-based benefits of companion planting with basil, as highlighted by numerous studies and expert sources, showcase the effectiveness of this sustainable gardening practice. Whether you’re a seasoned gardener or a novice enthusiast, incorporating these companion planting strategies can elevate your gardening experience and bring you closer to a bountiful and flavorful harvest. Embrace the power of basil and unlock the full potential of your garden!