sweet alyssum flowers

What Are Insectary Plants? How to Attract Beneficial Insects to Your Garden

Most gardeners think of flowers as something you grow for beauty or pollinators. Bees visit them for nectar, butterflies stop by for a meal, and hummingbirds occasionally join the party.

But some plants serve another important purpose entirely.

Insectary plants attract and support beneficial insects that hunt, parasitize, or otherwise control common garden pests. Instead of feeding your tomatoes to aphids and reaching for insect sprays, you can recruit an army of tiny predators and parasitoids that work for free.

A well-designed insectary can reduce pest problems, improve pollination, and make your garden more resilient.

What Is an Insectary Plant?

An insectary plant provides food, shelter, or habitat for beneficial insects.

Many predatory insects spend at least part of their lives feeding on nectar or pollen, even if their larvae or adults hunt other insects. Without those food sources, they often move elsewhere.

By planting species that support these beneficial insects, you encourage them to stay nearby and patrol your garden for pests.

Think of insectary plants as the equivalent of bird feeders and bird baths for your garden's insect predators.

Which Beneficial Insects Do Insectary Plants Support?

Many of the insects gardeners want most depend on flowering plants at some point in their life cycle.

Lady beetles consume huge numbers of aphids, scale insects, mites, and other soft-bodied pests.

Lacewing larvae hunt aphids, thrips, mealybugs, caterpillars, and insect eggs. Adults often feed on nectar and pollen.

Hoverflies may look like small bees or wasps, but their larvae rank among the most effective aphid predators in the garden.

Parasitic wasps lay their eggs inside or on pest insects such as caterpillars, aphids, whiteflies, and hornworms. Their larvae develop by feeding on the host insect.

Minute pirate bugs, soldier beetles, assassin bugs, and many predatory flies also benefit from insectary plantings.

Even some ants help by scavenging dead insects and preying on pest species, although others protect aphids in exchange for honeydew, so their role can vary from garden to garden.

Why Flowers Matter to Predators

Many beneficial insects cannot survive on prey alone. Adult hoverflies, parasitic wasps, lacewings, and predatory flies often need nectar as an energy source. Pollen supplies protein and nutrients that support reproduction.

Without these food sources, beneficial insects may visit briefly and disappear just when you need them most. A continuous supply of flowers keeps your pest control team close to the action.

milkweed

Insectary Plants by Region

Many insectary plants perform well across large parts of North America, but native and regionally adapted species often thrive in your local climate while supporting the greatest diversity of beneficial insects. That does not mean you need to limit yourself to plants from your own region. In fact, the most effective insectaries often combine native plants with flowering herbs and long-blooming annuals to provide food and habitat throughout the growing season.

Northeast and Mid-Atlantic

Sweet Alyssum grows as a low mound of tiny white, pink, or purple flowers that usually stays under 8 inches tall. It blooms for months and attracts hoverflies whose larvae consume large numbers of aphids.

Mountain Mint forms upright clumps of silvery green foliage topped with pale lavender-white flowers. Most varieties reach 2 to 4 feet tall. Few plants attract more beneficial insects, including parasitic wasps, predatory flies, and native bees.

New England Aster produces masses of purple flowers with yellow centers in late summer and fall on plants that typically reach 3 to 6 feet tall. It provides critical late-season nectar for beneficial insects preparing for winter.

Goldenrod sends up tall stems covered in brilliant yellow flowers from late summer into autumn. Depending on the species, plants range from 2 to 6 feet tall. Goldenrod attracts predatory wasps, soldier beetles, hoverflies, and many native pollinators.

Southeast

Coreopsis produces cheerful yellow daisy-like flowers on airy plants that typically grow 1 to 3 feet tall. It flowers heavily through summer and attracts hoverflies, small parasitic wasps, and pollinators.

Blanket Flower forms mounds of red and yellow blooms that resemble miniature sunsets. Most varieties stay between 1 and 2 feet tall. The long flowering season provides nectar for beneficial insects during the hottest months.

Yarrow grows ferny foliage beneath broad, flat flower clusters that appear in white, yellow, pink, or red. Plants usually reach 2 to 3 feet tall. The flat flowers make nectar accessible to tiny parasitic wasps and predatory flies.

hoverfly on chive flower

Midwest and Great Plains

Wild Bergamot produces shaggy lavender flowers on upright stems reaching 2 to 4 feet tall. It attracts predatory wasps, beneficial flies, native bees, and butterflies.

Prairie Sunflower grows 3 to 5 feet tall and produces bright yellow flowers that support pollinators while attracting predatory insects that feed on garden pests.

Golden Alexanders bloom in spring with clusters of yellow flowers held above leafy stems about 2 to 3 feet tall. Early-season flowers provide nectar when many beneficial insects first emerge from winter shelter.

Mountain West

Showy Milkweed produces pink flower clusters on sturdy plants that grow 2 to 4 feet tall. Besides supporting monarch caterpillars, the flowers attract many beneficial wasps and predatory insects.

Yarrow thrives in dry conditions and often grows naturally throughout western landscapes. Its broad flower heads provide easy access to nectar for tiny beneficial insects.

Penstemon sends up spikes of tubular flowers in shades of pink, purple, red, or white on plants that generally reach 1 to 3 feet tall. While hummingbirds love them, many native beneficial insects visit as well.

Pacific Coast

California Buckwheat forms soft gray-green mounds topped with creamy white flowers that gradually age to rust and cinnamon colors. Plants typically reach 2 to 4 feet tall and attract an enormous diversity of beneficial insects.

Coyote Mint produces lavender flower clusters on compact plants that usually remain under 2 feet tall. It blooms for long periods and supports predatory wasps and beneficial flies.

Douglas Aster grows 2 to 4 feet tall and produces masses of purple flowers late in the season when many insects need fuel before winter.

Herbs That Work Almost Everywhere

Some of the best insectary plants may already grow in your vegetable garden.

Flowering dill produces airy yellow umbels on plants 3 to 5 feet tall and attracts hoverflies and parasitic wasps.

Flowering fennel grows even taller, often reaching 5 to 6 feet, and draws huge numbers of beneficial insects throughout summer.

Bolting cilantro sends up delicate white flower clusters about 2 feet above the foliage and provides nectar for tiny parasitoid wasps.

Parsley allowed to flower produces umbrella-shaped blooms that attract many of the same beneficial insects while providing host plants for swallowtail butterfly caterpillars.

Umbel Flowers Are Insect Magnets

Plants in the carrot family deserve special attention. Dill, fennel, parsley, cilantro, and Queen Anne's lace produce flat clusters of tiny flowers known as umbels. These flowers provide easy access to nectar for very small beneficial insects, particularly parasitic wasps and hoverflies. You may notice these plants buzzing with activity throughout summer.

The insects you see visiting those flowers may spend the next few days searching your garden for aphids, caterpillars, and other pests.

Insectary Plants Work Best Throughout the Season

A single burst of spring flowers helps, but beneficial insects need food for the entire growing season. Early bloomers support insects emerging from winter shelter. Summer flowers sustain populations during peak gardening season. Late-season blooms provide resources before insects prepare for winter.

Aim for overlapping flowering periods from spring through autumn.

ladybeetle larvae

Do Not Judge Beneficial Insects by Their Babies

One challenge with supporting beneficial insects is that their young often look nothing like the adults. Ladybug larvae resemble tiny black and orange alligators covered in spikes and lacewing larvae look like miniature predators from a science fiction movie and sometimes camouflage themselves with the remains of the pests they eat. Hoverfly larvae resemble small maggots.

Many gardeners accidentally destroy these helpful hunters because they mistake them for pests. Before squishing an unfamiliar insect, take a moment to identify it. You may discover that it is working harder in your garden than you are.

Insectary Plants Reduce the Need for Pesticides

Broad-spectrum insecticides rarely distinguish between pests and beneficial insects. Unfortunately, the predators often die first because they reproduce more slowly than the pests they control. Aphids can rebound quickly after spraying, while the lady beetles and lacewings that once kept them in check may take weeks to recover.

Supporting beneficial insects creates a more stable system that often prevents pest outbreaks from becoming severe in the first place.

Small Plantings Can Make a Big Difference

You do not need an entire wildflower meadow to create an insectary. A few pots of sweet alyssum beside your vegetables, a patch of flowering herbs near your raised beds, or several native perennials mixed into ornamental borders can dramatically increase beneficial insect activity.

Much like a rain gauge helps you work with natural rainfall instead of guessing, insectary plants help you work with nature's own pest control system instead of fighting against it.

The most effective gardens rarely rely on a single solution. They build healthy soil, conserve water, support pollinators, and create habitat for the insects that quietly keep the ecosystem running.

Expand Your Beneficial Insect Knowledge

Back to blog