Certain insects are easily recognizable and universally loved. When we see a lady beetle going after a colony of aphids on a milkweed plant, or a praying mantis perched like a sentinel on a kale leaf, we smile and leave them to their good deeds.
However, many of the industrious do-gooders in our gardens take a little more effort to recognize and appreciate. Educating yourself about your backyard insect population may seem like a daunting project, but you’ll soon find yourself fascinated by the life-and-death drama that plays out every day on the leaves of your plants.
Here are some clues on how to encourage a healthy population of predators in your garden, so you can reduce or eliminate your use of pesticides:
L to R: Lacewing eggs; braconid wasp pupae; Carolina mantis egg case; lady beetle larva.
- Examine your plants frequently—predator insects are everywhere. Get in the habit of checking on your plants every day. Look closely and do your best to identify the insects you find, especially on the backs of leaves. Learn to recognize insect eggs, pupae, and larvae as well as the easily recognizable adults.
L to R: Braconid wasp larvae have emerged from a dead cabbageworm host and are pupating; Ichneumon wasps parasitize many different insect species; mason wasps paralyze their caterpillar prey and deposit them in chambers where they have laid their eggs.
- Welcome wasps. Most species of wasps are solitary and non-aggressive; many are parasitoids, that is, they lay their eggs in the bodies of cabbageworms, tomato hornworms, aphids, and other unwelcome garden inhabitants, ultimately killing them. Aggressive, ground-nesting yellow jackets give wasps a bad reputation that they do not deserve. Treat your backyard wasps well – most are gentle, helpful garden predators.
- Plant flowers! Perennials such as golden marguerite (Anthemis tinctoria), goldenrod and mountain mint (Pycnanthemum spp.), and annuals of many kinds provide resources for predator insects. Here’s a short list of easy-from-seed blooms that predator insects love.
Sweet alyssum (Lobularia maritima) attracts syrphid flies – and their aphid eating larvae.
Cilantro is favoured by lady beetles, lacewings, syrphid flies, and parasitic wasps.
Milkweed species draw pollinators of all kinds and often attract aphids in late summer, which bring in lady beetles and other aphid predators.
Bachelor’s Buttons (Centaurea cyanus) is favored by lacewings, parasitic wasps, syrphid flies, and lady beetles, and other helpful insects.
Dill attracts many species of predator wasps.
Anise hyssop (Agastache spp.) is especially attractive to parasitic wasps.
L to R: Kale and baby’s breath; chard in the flower garden; lollo rosa lettuce, beautiful and tasty
- Mix it up. Rather than planting multiple rows of brassicas (a clarion call to cabbageworms!), put a few here, a few there. Peppers, small-stature tomatoes, chard, lettuce and kale are a few vegetables that make interesting additions to the ornamental garden.
And last but not least:
L to R: The brown “aphid mummies” in this aphid colony indicates the presence of wasp parasitoids. A syrphid fly larva is also helping to keep this population in check; on the back of a kale leaf a tiny braconid wasp prepares to lay eggs in a cabbageworm.
Reposted with permission from: Home Garden Seed Association (HGSA) | P.O. Box 93 | Maxwell, CA 95955