Certain bugs beneficial to gardens
by Ellen Goff
Why have beneficial insects become the current topic of popular gardening conversations? Savvy gardeners across the Southeast know why.
The region's long growing season offers comfy conditions for many unwanted pests — insects that chew and suck the life out of food crops and flowers. Then there are the "beneficial" predator insects, which curb the damage and often eliminate infestations by doing what they do naturally, devouring the unwelcome critters.
You don't have to love bugs to care about beneficial insects. You don't even have to like them to appreciate their value. You just need to know what they look like throughout their life cycle and have a rough idea of the pests they prey upon. Look to these garden workers as informants on the conditions in your yard. You may see a good bug before you notice any damage from a bad one.
The idea of having beneficials patrolling your garden, keeping pests in check, may seem a little theoretical until you witness the results firsthand. It was that way for me.
Prior to my first encounter, I never made any provisions for attracting them besides eliminating pesticide use. I figured there were probably going to be more bugs around, but it was better than poisoning myself.
So one morning, on my daily tomato patch inspection, I was shocked and dismayed to find several plants reduced to stems — not a leaf to be seen. These plants were lush and vigorous just a day before. It took me a while to locate the camouflaged culprit: a tomato hornworm. I spent most of the day thinking about what to do.
When I returned to the patch, the hornworm had rice-size things, actually minute cocoons, covering its back. I sensed a force of nature at work. The next day, the pest was gone. I had witnessed the work of a predator — in this case a parasitic wasp — on its prey, the hornworm.
This simple phenomenon seemed like pure magic to me. From that day forward, I committed myself to working with beneficials by following a few easy steps:
- Don't use chemical pesticides in your yard.
- From spring through fall, keep a variety of easy-care plants blooming to attract beneficials — many of them well-suited to the heat and humidity of our southern and coastal climates, including: ajuga, bee balm (monarda), butterfly weed, cilantro, columbine, dill, English lavender, fennel, goldenrod, mint, penstemon, salvia, sedum, sweet alyssum, thyme, yarrow, veronica.
To identify valuable insects, it helps to know what pests might be present based on the plants in your yard. For example, in spring and early summer, aphids descend on flower buds and stems of both food crops and ornamentals. This soft body pest is a tasty repast to a number of beneficials. The one you can probably recognize easily is the lady beetle.
For more photos of beneficials, refer to your local Cooperative Extension website or click on the U.S. Department of Agriculture and University of Georgia sponsored site insectimages.org.
Ellen Goff is a freelance horticulture writer and photographer. She's passionate about plants, water quality and protecting the environment. Aside from working with words and pictures, she stays busy with her home landscape and its inhabitants along the shores of Lake Wylie, S.C.