Attracting pest-devouring beneficials to your garden
Story and Photos by Kristi Cook
I don’t know about where you live, but in my neck of the woods fall brings swarms of Asian lady bugs, clinging desperately to my home, vehicles, trees, kids, and even pets. They creep their way into my windows, nestle deep inside every nook and cranny, and crawl in my hair when my path crosses theirs. And while this is, at times, a bit of a nuisance, I remind myself that these little guys are simply trying to find a safe winter hideout until they can venture out again to devour any aphids brave enough to attack my garden. However, ladybugs aren’t the only pest-fighting soldiers out there. Lacewings, hover flies, and parasitic wasps are just a few of the predatory insects worth enticing to your garden.
Beetles
Of all the beneficial beetles roaming the garden, lady beetles, aka ladybugs, are the most easily recognized garden warriors. Best known as aphid hunters, a single ladybug is capable of cleaning an entire tomato plant of aphids in a single day. Yet the ladybug is just one example of a pest-eating beetle. The large, shiny, black ground beetle is an often-overlooked ally, yet it will happily devour slugs, snails, and caterpillars if left alone. Typically nocturnal hunters, these lumbering beetles prefer to stay cozy under a bed of cool mulch during the hot daytime hours or lounge in the cool shade of a nearby tree until the sun goes down. But don’t worry about planting a shrub or flowers for these guys. Just provide the mulch and refrain from squashing them, and they should stick around.
Lacewings
Dainty lacewings look like tiny green or brown fairies flitting around the garden. And while some species of adult lacewings do enjoy the occasional insect meal, it’s the larvae, aptly named aphid lions, that you really want. These hungry guys devour aphids, mites, thrips, caterpillars, and even the occasional beetle in their quest to reach adulthood. Lacewings are drawn to many of the same delicate flowers as the lady beetles such as fern-leaf yarrow (Achillea filipendulina), common yarrow (A. millefolium), and butterfly weed (Asclepias tuberosa), yet they also enjoy prairie sunflower (Helianthus maximiliani), Cosmos, and tansy (Tanacetum vulgare).
The true beauty of attracting pest-eating beneficial insects is its simplicity.
Hoverflies
Often mistaken for a tiny bee, the stingless hoverfly is a predatory fly whose larvae enjoy a quick meal of aphids, mealybugs, and other small insects. These babies are so hungry, a single larva is capable of consuming up to 400 aphids in a single day! To attract the nectar-drinking adults, intersperse various plantings of Calendula, Cosmos, Queen Anne’s lace (Daucus carota), and yarrow (Achillea spp.).
Parasitic Wasps
Braconid, ichneumon, and trichogramma wasps are but a few of the parasitic wasps eager to devour garden pests. Some parasitic wasps deposit eggs on the outside of caterpillars while others deposit eggs within the eggs of pests. Regardless of the method, these tiny wasps rarely have stingers, yet offer an abundance of pest control. Adult wasps are attracted to rosemary (Rosmarinus spp.), fennel (Foeniculum vulgare), mustard (Brassica spp.), and nectar from a wide variety of flowering plants.
The true beauty of attracting pest-eating beneficial insects is its simplicity. Requiring little more than nectar-rich flowers, a pesticide-free environment, and a few pests to devour, beneficials will happily take up residence in your yard and garden. Many of these predatory insects play another important role in your garden as pollinators – making them even more beneficial!
Send Out Invites!
The greater the variety of nectar producing flowers the better. Most beneficials are attracted to multiple types of flowers with most flowers attracting multiple species of predatory or parasitic insects. Native predators are attracted to native plants, so be sure to also include these in your predator-attracting plan.
A very brief list of plants to attract beneficial predators:
Dill (Anethum graveolens)
Yellow coneflower (Ratibida pinnata)
Purple poppy mallow (Callirhoe involucrata)
Fennel (Foeniculum vulgare)
Dandelion (Taraxacum officinale,)
Spike speedwell (Veronica spicata)
Hairy vetch (Vicia villosa)
Yellow giant hyssop (Agastache nepetoides)