Our Favorite Companion Flowers to Plant in the Garden (and a Few Things To Watch Out For)

Companion planting isn’t just about which veggies go well together—it’s also about inviting the right flowers into your garden. Flower companions can boost pollination, deter pests, attract beneficial insects, and even improve soil health. Plus, let’s be honest: flowers bring the kind of joy to a garden that no bug-eaten kale leaf ever could.

Here are our favorite tried-and-true companion flowers and exactly why they deserve a spot in your garden. We’re also sharing some key tips and cautions to help you get the most out of these blooms.

Zinnias

Why we love them: Zinnias are reliable bloomers that bring serious color to the garden—and more importantly, they attract pollinators like bees, butterflies, and hummingbirds in droves. Their open-faced blooms make nectar and pollen easy to access, which is great for busy pollinators. They also pull in beneficial predatory insects like ladybugs and lacewings, which are natural enemies of aphids and thrips.

Watch out for: Zinnias are prone to powdery mildew, especially in humid climates or when spaced too closely.

Pro tip: Provide good airflow, avoid overhead watering, and remove affected leaves promptly. Deadhead regularly to keep blooms coming and beneficials buzzing.

Cosmos

Why we love them: Cosmos are a pollinator favorite and bloom for months with minimal care. Their lacy foliage and airy blooms attract helpful insects like lacewings and parasitic wasps—both of which help reduce pest populations. They also provide nectar to native bees and butterflies, extending pollinator support well into the season.

Watch out for: Cosmos can reseed heavily if left to go to seed, which can be great… or overwhelming.

Pro tip: Plant cosmos near crops like tomatoes, corn, or cucumbers to increase pollinator visits and invite natural pest control. Thin volunteers in the spring to manage spread.

Alyssum

Why we love it: Low-growing and fragrant, sweet alyssum is a multitasking ground cover. It helps suppress weeds, reduces soil evaporation, and provides nectar for beneficial insects like hoverflies and tiny parasitic wasps—both of which target aphids. It’s also excellent at filling in the gaps between veggie rows or at the edges of beds.

Watch out for: Alyssum can spread and reseed freely, especially in warm zones.

Pro tip: Use it as a living mulch under taller crops like broccoli or tomatoes. Trim back after blooming to encourage another flush and prevent it from getting leggy.

Nasturtium

Why we love them: Nasturtiums are one of the best-known “trap crops.” Their tender leaves are irresistible to pests like aphids, cabbage loopers, and squash bugs—drawing them away from more valuable plants. They also attract predatory insects and pollinators and are completely edible, with a spicy, peppery flavor.

Watch out for: Heavy infestations can take over nasturtiums quickly. They’re sacrificial, but don’t let them harbor pests unchecked.

Pro tip: Use nasturtiums near cucurbits (zucchini, squash, cucumbers), brassicas, or beans. Once pest pressure builds up, pull and replace affected plants.

Calendula

Why we love them: Often called “pot marigold,” calendula is a powerhouse pollinator plant that also supports pest control. It attracts ladybugs, lacewings, hoverflies, and parasitic wasps—key players in managing aphids, thrips, and caterpillars. The sticky resin on its stems can even trap small pests. As a bonus, its petals are edible and have soothing medicinal properties.

Watch out for: Calendula reseeds easily and can sprawl if not trimmed back.

Pro tip: Plant calendula throughout your garden, especially near tomatoes, carrots, and leafy greens. Cut it back to encourage new blooms and contain growth.

Canada Goldenrod

Why we love it: This native wildflower is one of the most beneficial late-season bloomers, offering nectar and pollen when other flowers fade. It supports dozens of native bees, butterflies, and beneficial insects like soldier beetles and parasitoid wasps. It’s also a key plant for native biodiversity.

Watch out for: Canada goldenrod spreads aggressively through underground rhizomes and can become invasive if not managed.

Pro tip: Grow goldenrod in a designated pollinator zone or container to prevent it from invading your veggie beds. Avoid planting near shallow-rooted crops like lettuce, radishes, or carrots.

French Marigolds

Why we love it: French marigolds are pest-fighting champions. Their roots release thiophenes, natural compounds that suppress harmful nematodes in the soil. Their strong scent also repels aphids, whiteflies, and even rabbits. Plus, they attract pollinators and predatory insects like hoverflies.

Watch out for: Some hybrid varieties don’t have the same pest-repelling benefits—stick to traditional French marigold types.

Pro tip: Interplant marigolds with tomatoes, peppers, beans, or squash. Bonus: they add bold color and scent to your beds while quietly working behind the scenes.

Borage

Why we love it: Borage is a dynamic companion. Its star-shaped blue flowers are beloved by bees, and its large, hairy leaves improve soil when chopped and dropped as green mulch. Some gardeners swear it enhances the flavor and vigor of nearby strawberries and tomatoes. It’s also a trap crop for tomato hornworms.

Watch out for: Borage self-seeds prolifically and can get quite large. Mature plants are heavy feeders.

Pro tip: Thin seedlings early and plant near tomatoes, strawberries, or squash. Let a few plants go to seed each year to keep it in the rotation without it taking over.

Lavender

Why we love it: Lavender is both beautiful and functional. Its aromatic oils deter pests like moths, mosquitoes, and fleas, and its nectar-rich flowers draw bees and butterflies all summer. It thrives in dry, low-fertility soils and can provide a natural pest barrier when planted around beds or borders.

Watch out for: Lavender hates wet feet. Overwatering or planting in heavy soil can lead to root rot.

Pro tip: Plant lavender near brassicas or carrots to confuse pests, and prune annually to keep plants compact and productive.

Sunflowers

Why we love them: Tall and striking, sunflowers serve as natural trellises for climbing crops like beans and can provide helpful shade for lettuce or spinach during hot months. They attract bees, parasitic wasps, and other beneficial insects and help loosen soil with their strong, deep taproots.

Watch out for: Sunflowers release allelopathic chemicals that can inhibit germination and growth of nearby plants—especially shallow-rooted veggies.

Pro tip: Plant sunflowers in their own space or at the edge of the garden, away from crops like lettuce, spinach, or carrots. After the season, chop and compost the stalks or use them as bean poles the next year. We plant ours in a raised section behind our garden with pumpkins. Best pumpkin yeild we’ve ever had!

Adding flowers to your veggie garden isn’t just about aesthetics—it's about building a stronger, more balanced ecosystem. When you choose the right flowers and pair them thoughtfully with your vegetables, your garden becomes a magnet for pollinators, a fortress against pests, and a more joyful place to be.

So go ahead and plant those zinnias, tuck in some marigolds, and let the nasturtiums run wild (just a little). Your garden will thank you.