Sweet Pea Companion Plants

Choosing the right sweet pea companion plants can make a huge difference in your garden’s health and beauty. These ideal garden partners help your sweet peas climb, bloom, and resist pests naturally.

Companion planting is a smart way to work with nature. It creates a balanced ecosystem where plants support each other. For sweet peas, good companions can provide structure, improve soil, and attract helpful insects. This leads to more flowers and a happier garden for you.

Let’s look at the best plants to grow alongside your sweet peas. These partners are chosen for their practical benefits, from offering support to fighting off bugs.

Excellent Support Plants

Sweet peas are climbers. They need something sturdy to hold onto. While you can use trellises, living supports are a beautiful alternative.

Corn: Tall corn stalks make a perfect natural trellis. The sweet peas will climb the stalks, and their flowers look lovely against the green leaves.
Sunflowers: Choose a tall, sturdy variety. Sunflowers provide a strong stem for sweet peas to twine around. The contrast between the large sunflower heads and delicate sweet pea blooms is stunning.
Jerusalem Artichokes (Sunchokes): These perennial plants grow very tall and thick. They create a living fence that supports sweet peas and provides wind protection.

Beneficial Flower Companions

Flowers aren’t just pretty. They bring in pollinators and predatory insects that protect your garden.

Nasturtiums: These are a top choice. Nasturtiums attract aphids away from your sweet peas, acting as a “trap crop.” Their bright flowers also draw in pollinators.
Calendula: Known for repelling certain pests like asparagus beetles. Calendula’s sticky stems can even trap small bugs, and they bloom for a long time.
Alyssum: This low-growing flower forms a fragrant carpet. It attracts hoverflies, whose larvae are voracious aphid eaters. Planting alyssum at the base of your sweet peas is a great strategy.
Lavender: Its strong scent is known to deter rabbits and deer. Lavender also attracts bees and butterflies from far and wide, which helps with pollination of other plants.

Helpful Vegetable Partners

Many vegetables grow well with sweet peas, creating a productive and attractive garden bed.

Leafy Greens (Lettuce, Spinach): Sweet peas provide light shade for these cool-weather crops, preventing them from bolting too quickly in the summer heat.
Root Vegetables (Radishes, Carrots): These grow underground and don’t compete with the shallow roots of sweet peas. They help break up the soil, making it easier for all plants to grow.
Nightshades (Tomatoes, Peppers): This is a classic partnership. Sweet peas fix nitrogen in the soil, which these heavy feeders love. Just ensure the sweet peas have their own support so they don’t smother the vegetables.

Herbs to Plant Nearby

Herbs are powerful companions. Their strong oils and scents confuse and repel many common garden pests.

Rosemary: Its pungent smell deters bean beetles and carrot flies. It’s a woody perennial that needs well-drained soil, just like sweet peas.
Dill: Attracts ladybugs and parasitic wasps that control aphid populations. It’s a fantastic friend for any plant plagued by sap-sucking insects.
Chives & Garlic: Their allium scent repels aphids and can even help prevent fungal issues. They are easy to grow and fit in small spaces around your sweet pea base.

Plants to Avoid Near Sweet Peas

Not all plants get along. Some can inhibit growth or share diseases. Keep sweet peas away from:

Alliums (Onions, Garlic, Chives): While chives and garlic can be helpful, some gardeners find strong alliums stunt the growth of peas and beans. It’s best to observe in your own garden.
Gladiolus: These flowers are known to compete vigorously for nutrients and can hinder the growth of nearby plants like sweet peas.
Other Legumes: Avoid planting them with beans or regular peas. They are in the same family and can share diseases and pests more easily.

How to Plant Your Sweet Peas with Companions

Planning is key. Follow these steps for a successful, intertwined garden bed.

Plan Your Layout: Sketch your garden. Place tall support plants (corn, sunflowers) on the north side so they don’t shade shorter plants. Put sweet peas in front of them to climb.
Prepare the Soil: Sweet peas love rich, well-drained soil. Add plenty of compost before planting. Avoid high-nitrogen fertilizers, as sweet peas produce their own.
Plant in Succession: Sow sweet pea seeds directly in early spring. Plant quick-growing companions like radishes and alyssum at the same time. Add transplants like tomatoes and herbs after the last frost.
Provide Initial Support: Even with living supports, give young sweet peas some string or small sticks to guide them toward their companion plant.
Water and Mulch: Water at the base to keep foliage dry and prevent mildew. Apply a light mulch to retain moisture and suppress weeds, which can compete for resources.

Maintenance Tips for a Mixed Planting

A little care goes a long way. Keep these points in mind during the growing season.

Regular Harvesting: Pick sweet pea flowers often. This encourages more blooms and prevents the plant from putting energy into seed production.
Monitor for Pests: Check the undersides of leaves, especially on nasturtiums (your trap crop). Remove aphid clusters by hand or with a strong spray of water.
Feed Lightly: If needed, use a balanced, organic fertilizer. Remember, sweet peas add nitrogen, so you may not need to feed as much.

The Science Behind the Pairings

Companion planting works for several real reasons. Understanding them helps you make your own good choices.

Nitrogen Fixation: Sweet peas are legumes. They work with bacteria in there roots to take nitrogen from the air and convert it into a form plants can use. This enriches the soil for neighboring plants.
Pest Confusion & Trapping: Strong scents from herbs mask the smell of sweet peas, confusing pests. Trap crops like nasturtiums are more appealing to pests, luring them away.
Habitat for Beneficials: Flowers provide nectar and pollen for insects like ladybugs, lacewings, and hoverflies. These insects then lay eggs near aphid colonies, and their larvae eat the pests.
Physical Support & Microclimates: Tall plants create shelter from wind and sun. Low-growing plants act as a living mulch, keeping soil cool and moist for shallow sweet pea roots.

Designing a Beautiful Companion Garden

Think about color, height, and texture. Your garden can be both productive and gorgeous.

Combine blue and purple sweet peas with orange calendula and yellow nasturtiums for a vibrant, warm palette. For a cooler, calming look, pair white and pink sweet peas with lavender and white alyssum. Use the vertical space with your support plants, then layer down in height with mid-level herbs and low ground cover flowers. This creates a full, lush appearance.

FAQ: Sweet Pea Companions

What grows well with sweet peas?
Many plants do! Good companions include corn, sunflowers, nasturtiums, calendula, alyssum, lettuce, spinach, radishes, tomatoes, rosemary, and dill.

Can you plant marigolds with sweet peas?
Yes, French marigolds are an excellent choice. They repel nematodes and other soil pests with there roots. Their scent also deters above-ground insects.

Where is the best place to plant sweet peas?
Choose a spot with full sun (at least 6 hours), well-drained soil, and good air circulation. They need something to climb on, like a trellis or a companion plant.

What should you not plant next to sweet peas?
It’s generally advised to avoid other legumes (beans, peas), strong alliums like onion, and gladiolus, as they may compete or share diseases.

Do sweet peas add nitrogen to soil?
Yes, they are nitrogen-fixing plants. They improve soil fertility for other plants, making them a wonderful pre-plant for heavy feeders like tomatoes.

How do you keep sweet peas blooming?
Pick the flowers regularly, never letting them go to seed on the plant. Ensure they have adequate water, especially as temperatures rise, and provide some afternoon shade in very hot climates to prolong the blooming season.

By choosing the right sweet pea companion plants, you create a resilient and beautiful garden. This method reduces the need for chemicals and increases your overall harvest. Start with a few pairings from this list and see how your garden thrives with these ideal garden partners working together.