Sweet Pea Companion Plants (herbs, flowers, and vegetables to plant in your garden)

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Imagine walking through a friend’s garden, captivated by the vibrant, blooming sweet peas that seem to dance in the sunlight. Inspired, you decide to introduce these beauties to your garden space and ponder the best sweet pea companion plants you can sow alongside.

Sweet peas thrive when paired with plants like marigolds, which deter pests, and beans that fix nitrogen in the soil. Avoid planting sweet peas near onions or garlic, as they can hinder growth. Use trellises for support and ensure good spacing for best results.

blooming pink and purple sweet pea flowers in small glass vase

Diving into the world of companion planting for sweet peas could be the game-changer your garden needs.

In this article, you’ll discover the symbiotic and beneficial relationships in nature where specific plants benefit each other in fascinating ways and the advantages of sweet pea companion planting while learning what might not be the best neighbor for your sweet peas.

Humble Highlights

  • Explore the art of companion planting with sweet peas to discover how to create a flourishing garden ecosystem with sweet peas as the centerpiece.
  • Discover the ideal companion plants for sweet peas in your garden so you can watch them grow harmoniously alongside your other garden foliage.
  • Save time and money by discovering these unique and essential sweet pea companion planting tips so you can enhance your green space for a prosperous and flourishing garden!

Growing And Planting Sweet Peas 

Sweet peas (Lathyrus odoratus) are vibrant members of the Fabaceae family, primarily grown for their aromatic, colorful blossoms. Their hues range from delicate whites to deep purples, enhancing garden spaces and serving as exquisite cut flowers.

companion planting with sweet peas

Sweet peas thrive in cool weather with well-draining soil and require a trellis or support due to their climbing nature, ensuring their tendrils ascend gracefully. Their captivating fragrance and visual appeal make them a prime choice for many backyard gardeners as they grow. 1

Humble Tip:

While they both carry the ‘pea’ moniker, garden peas – which gardeners cultivate for consumption and provide beneficial nitrogen to the soil – are distinct from sweet peas. 

All parts of the sweet pea plant are toxic if ingested. These plants serve primarily ornamental purposes, and their intoxicating aroma should remind us that, though they are a feast for our eyes and noses, they are not meant for consumption.

Benefits Of Companion Planting For Sweet Peas

Improved Pest Control

Companion planting for sweet peas introduces repellent plants to help keep pea pests such as aphids, thrips, and pea moths in check. These companion plants also attract beneficial insects like the humble ladybug, providing a holistic and protective approach to garden care. 2

Enhanced Pollination

Pairing sweet peas with other plants known for attracting bees, like Borage, Calendula, and Thyme, can significantly enhance pollination. These companion plants draw pollinators, ensuring that the sweet peas will benefit from their flowers’ increased yield and quality.

companion plants for sweet peas

Incorporating Sweet Pea: Companion Planting Guide

Choosing The Right Location And Layout

Finding a sunny location is paramount if you pair sweet peas with corn as companions. While sweet peas appreciate partial shade during hotter parts of the day, corn thrives in full sun. They grow together more effectively by selecting a location where both plants can receive the sunlight they require.

In an east-west configuration, the sweet peas and corn are planted in rows parallel to each other, with the sweet peas facing east and the corn facing west. This configuration allows the sweet peas to receive the morning sun and the corn to receive the afternoon sun.

In a north-south configuration, the sweet peas and corn are planted in rows running perpendicular to each other, with the sweet peas facing north and the corn facing south. This alignment allows the sweet peas to receive full sun throughout the day and the corn to receive partial shade.

companion planting sweet peas

Timing And Spacing Considerations

When planting sweet peas alongside carrots, giving them adequate space is essential. Sweet peas might be sown in early spring, while friendly companion carrots can be planted several weeks later. Maintaining approximately 8-12 inches of distance from pea roots ensures that both plants have ample room to develop and helps these plants germinate without hindrance.

Tips For Watering And Maintaining Companion Plants

If you’re growing sweet peas alongside Borage, both plants can benefit from consistent watering schedules, as neither likes to dry out completely. Borage, known for its vibrant blue flowers and a friendly companion to many garden plants, can enhance the soil with added minerals such as potassium, calcium, and magnesium. Regular pruning and checking for pests will help your sweet peas and Borage grow more productively. 3

companion planting for sweet peas

Potential Challenges Of Companion Planting With Peas

Competition For Resources

Plants such as squash or zucchini can be heavy feeders, meaning they draw a lot of valuable nutrients and water from the soil. If sweet peas are planted alongside and without appropriate soil replenishment, they might struggle due to nutrient competition.

While sweet peas need regular watering, planting them next to excessively water-loving plants such as celery or watercress might result in water competition, especially if garden space is limited. 4

Humble Tip:

It’s essential to ensure that sweet peas have ample space and nutrients, particularly when companion planting. Providing adequate spacing, understanding the specific needs of each plant, and annually rotating crops to different beds or plots can help manage these competition challenges and encourage better, healthier growth.

Cross-Pollination Issues

If you grow sugar snap peas close to another pea variety, such as snow peas, cross-pollination is possible. Unfortunately, this process can result in unwanted hybrid seeds, affecting how peas grow in the subsequent seasons.

Disease Management

While tomatoes, for example, might help deter certain pests, if peas don’t have an immune response to specific diseases that tomatoes might carry (like blight), it could result in both plants succumbing to illnesses. Proper spacing, regular monitoring, and taking action if needed can alleviate these risks.

Best Companion Plants For Sweet Peas (Herbs, Flowers, and Vegetables)

Pairing two plants together can create a harmonious environment that promotes healthy plants. Dive into the best companion plants for sweet peas, spanning flowers, vegetables, and herbs to optimize your garden’s potential.

sweet peas companion vegetables

Best Herbs To Plant Near Sweet Peas

Dill Attracts Ladybugs 

Dill is an exceptional choice as a companion for sweet peas because it tends to grow well with peas, enhancing their growth environment. Not only does dill attract beneficial insects like ladybugs and parasitic wasps, which prey on potential garden pests, but its presence also acts as a deterrent to some pests that target sweet peas, like aphids, cabbage moths, and flea beetles.

Interestingly, the aromatic nature of dill can mask the scent of nearby plants and help shield them from those pests. Additionally, dill’s feathery foliage creates a natural mulch that helps retain moisture in the soil, reducing the need for frequent watering. 5

Dill proliferates quickly and provides shade for young sweet pea seedlings, helping them establish roots before exposure to full sun. Additionally, dill’s tall stems support climbing sweet peas, preventing them from falling over or tangling.

companion plants for sweet pea flowers

Rosemary Repel Whiteflies 

This aromatic herb is renowned for its pest-repelling qualities, ensuring that when grown adjacent to sweet peas, it can be a natural deterrent against insects like mosquitoes, aphids, and whiteflies that might otherwise target peas alone.

Furthermore, rosemary doesn’t have demanding nutrient requirements that would compete with sweet peas, allowing both plants to flourish. As a result, the combined presence of rosemary and sweet peas creates a symbiotic relationship where peas grow well, shielded from many potential threats from pests and diseases such as powdery mildew.

Humble Tip:

Powdery mildew is a fungal disease that affects many plants, manifesting as fine white, powdery spots on leaves and stems. Left untreated, it can spread quickly throughout your garden, stunting plant growth and reducing fruit and flower production.

Thyme As Slug Repellent

Thyme’s aromatic properties help repel certain pests from sweet peas, including damaging slugs, snails, cabbage worms, and aphids. The low-growing nature of thyme ensures it doesn’t compete aggressively with sweet peas for space or resources, while its scent can mask the presence of peas, further shielding them from these harmful pests. 6

Growing your backyard sweet peas doesn’t have to be complicated. It just takes a little effort, and some tried and true steps to get your plants off on the right start. Check out the video below that details how you can get your sweet peas up and going in short order!

Top 3 Flowers To Plant Alongside Sweet Peas

Nasturtiums As Trap Crop

When you plant these beautiful blooms alongside sweet peas, they are a natural deterrent against harmful pests such as aphids and certain beetles like Mexican bean and Colorado potato beetles.

Additionally, nasturtiums can be a trap crop, enticing pests to feast on them instead of the sweet peas. These types of plants that help divert potential threats make them the perfect companions for ensuring the health and vitality of sweet peas within your garden space.

Humble Tip:

A trap crop is a plant that is intentionally grown to lure pests away from other crops. Pests are attracted to the trap crop, where they feed and reproduce, leaving the primary crop unharmed. Trap cropping is a strategy used in integrated pest management programs to reduce damage to valuable crops. It is an invaluable tool countless backyard growers use to protect their fruitful yields. 7

Marigolds For Nematode Free Environment

These bright and cheery flowers are renowned as companion plants that offer a two-fold benefit for many plants, including sweet peas. Firstly, specific marigold varieties’ roots release toxic substances to harmful nematodes and soil-dwelling worms.

can you grow peas and sweet peas together

Nematodes, specifically plant-parasitic nematodes, feed on plant roots, causing damage, reducing nutrient uptake, and often leading to stunted growth and reduced yields. Their feeding sites can also provide entry points for fungi and bacteria, leading to secondary infections and further compromising plant health.

Fortunately, marigolds help foster a nematode-free environment, especially for plants that need more sanitized soil, like sweet peas. Moreover, the repellent qualities of marigolds safeguard sweet peas from pests such as whiteflies, aphids, and spider mites, classifying them as perfect companion flowers.

Calendula (Pot Marigold) Deters Aphids

The vibrant Calendula flowers attract beneficial insects like ladybugs and keep certain pests at bay with their strong scent, such as aphids, whiteflies, and nematodes.

Calendula blooms ensure that sweet peas remain protected from potential fungal diseases, including powdery mildew, downy mildew, and rust, proving their worth as valuable companion plants that must be included in a sweet pea garden for optimal health.

Vegetable Plants That Grow Well With Sweet Peas

Radishes As Protective Barrier From Pests

Radishes make great companions for sweet peas because they help deter certain pests that might target them, including flea beetles, aphids, and slugs. Additionally, with their deep, penetrating roots, radishes can help loosen compacted soil, allowing for better drainage and aeration, vital for consistent sweet pea growth.

sweet pea companion vegetables

As for the protective barrier, radishes can help shield sweet peas from certain pests that might otherwise damage the plants. For example, radishes can help deter slugs and snails, which can cause significant damage to sweet pea seedlings when germinating. Additionally, radishes can help attract beneficial insects into your garden, such as ladybugs, which can help control harmful pest populations.

Cucumbers As Heavy Feeders

Both cucumbers and sweet peas have complementary growth habits that ensure they don’t compete heavily for soil nutrients. They grow together harmoniously, with young cucumber plants benefiting from the partial shade provided by the taller sweet peas.

Sweet peas fix atmospheric nitrogen with the help of rhizobia bacteria and deposit this valuable nutrient to the ground, enriching your garden soil. Cucumbers, being heavy feeders, thrive with this added nitrogen. Moreover, the tall growth of sweet peas provides a natural trellis for vining cucumbers, keeping them off the ground and less prone to pests and rot. 8

Humble Tip:

Rhizobia bacteria are symbiotic bacteria that form nitrogen-fixing nodules on the roots of leguminous plants, such as beans and sweet peas. They convert atmospheric nitrogen into ammonia, which is then absorbed by the plant and used for growth. This process is called nitrogen fixation and is crucial for plant nutrition, especially within soils low in nitrogen.

Beans As Nitrogen Fixers

Varieties like snap beans, bush beans, and green beans make excellent companion plants for sweet peas due to their mutual ability to enrich the soil. Both beans and sweet peas are leguminous plants that fix nitrogen in the ground, essential for robust plant growth.

Both beans and sweet peas can attract beneficial insects, such as bees, which can aid in necessary pollination, further enhancing the garden’s health. Taller sweet pea vines can provide shade for heat-sensitive bean plants during the hottest parts of the day. Additionally, sturdy bean stalks can offer support for neighboring sweet pea tendrils.

Plants To Avoid Planting Near Sweet Peas

While a row of peas can thrive with the right neighbors, certain plants might not be so friendly or beneficial when planted nearby. Discover which plants to steer clear of to ensure your sweet peas flourish unhindered.

what not to plant with sweet peas

Onions And Garlic’s Allelopathic Properties

These unique plants can deter some beneficial insects that sweet peas attract, including bees, butterflies, and ladybugs. They also have different soil nutrient requirements, which might lead to competition as your plants mature.

Both onions and garlic release substances into the soil such as disulfides, trisulfides, and isothiocyanates that exhibit allelopathic properties, which means they can suppress sweet pea seed germination, hinder root development, and disrupt nutrient absorption, leading to stunted growth, weakened enzymatic functions, and increased vulnerability to pests and diseases.

Humble Tip:

Disulfides, trisulfides, and isothiocyanates are sulfur-containing compounds formed by breaking down proteins and other biological molecules. They are known for their strong odor and flavor and are commonly found in foods such as garlic, onion, and cruciferous vegetables. 

Garden Peas Vulnerability To Pests And Diseases

Garden peas and sweet peas, being from the same family, share vulnerabilities to certain pests (aphids and thrips) and diseases. When planted close together, they can serve as a continuous buffet for pests, allowing easier migration from one plant to the next. Additionally, certain soil-borne diseases can thrive and multiply when their preferred hosts are abundant and closely spaced.

what can i plant next to sweet peas

For instance, diseases like Fusarium wilt and root rot can affect garden and sweet peas. If one plant becomes infected, having a similar host nearby means the disease has a shorter distance to travel, potentially leading to a faster spread among your foliage and making it more challenging to manage and eradicate the problem. Thus, diversifying plantings by separating these legumes can help disrupt the life cycle of pests and pathogens and reduce overall risks – making your life easier!

The Allelopathic Fennel

Fennel is allelopathic, meaning it releases substances like anethole into the soil. Anethole and other allelopathic compounds released by fennel can have several detrimental effects on neighboring plants.

These substances can hinder seed germination, disrupt root growth, and stunt the overall development of sensitive plants, leading to diminished size and production. Furthermore, plants exposed to these chemicals often experience heightened vulnerability to pests such as aphids, whiteflies, and spider mites and diseases like root rot, mildews, rusts, and blights due to weakened defenses. 9

Humble Tip:

Anethole is a natural chemical found in fennel seeds. It is responsible for fennel’s characteristic aroma and flavor and is often used in cooking and baking. Anethole is also present in other plants, such as star anise and coriander. It may be considered safe for consumption in small amounts but should be avoided in more significant quantities due to its potential toxicity. If unsure, always consult your physician or medical professional first before ingesting.

what can be planted with sweet peas


Growing peas, especially sweet peas, can be a rewarding experience when done right. One key aspect of ensuring their vibrant blooms is understanding the significance of companion planting, which can enhance the beauty of your garden by creating a more diverse and exciting landscape.

As we’ve explored, sweet peas provide an environment where certain plants benefit immensely. Choosing the proper companions can lead to healthier plants, natural pest control, and an enriched soil environment. Sweet peas’ companion plants include cucumber, beans, calendula, dill, and thyme, but don’t plant them alongside onions, garlic, and fennel.

When your peas are ready to be introduced to your garden, remember the invaluable companions that aid their growth and those that might hinder it. By embracing the art of companion planting, you set your sweet peas on a path to thrive.

Do you currently cultivate companion plants with sweet peas in your backyard garden? We’d love to know what friendly plants you’ve chosen as happy neighbors. Drop us a line in the comment section below and let us know your success!


  1. Almanac – Sweet Peas
  2. MDPI – Application Of Trap Cropping As Companion Plants For The Management Of Agricultural Pests: A Review
  3. Cornell University, Cooperative Extension – Companion Planting
  4. Almanac – Companion Planting Chart And Guide For Vegetable Gardens
  5. Wikipedia – Dill
  6. National Library Of Medicine, National Center For Biotechnology Information – A Focused Insight Into Thyme: Biological, Chemical, And Therapeutic Properties Of An Indigenous Mediterranean Herb
  7. ScienceDirect – A First Approach To Pest Management Strategies Using Trap Crops In Organic Carrot Fields
  8. ASHS Journals – Pollinator-Attracting Companion Plantings Increase Crop Yield Of Cucumbers And Habanero Peppers
  9. Wikipedia – Fennel

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