You may be letting beneficial insects take care of your pest problems, but there are a few (and pretty) steps you can take to boost and maintain their population in your landscape. (If you’re new to the subject read Let Beneficial Insects Work for You in Your Garden—Here’s All They Need From You first.)
If you’re having a hard time finding any beneficials, or you have pest problems that are really pushing you to consider extreme measures—and if you like having a garden that takes care of things for you plus gives you nice flowers—here are some things you can do.
Keep the commute short for the good bugs
Since most predacious bugs (the beneficial insects) need both pests and flowers to feed on, keep their food sources near each other. If they have to go far between the pests and the flowers, they’ll live elsewhere or not at all. Be sure the best flowers for them are available in your gardens. All in the same landscape, or a close neighbor’s is good.
Create an insectary border or garden
More than planting some good flowers in your landscape, plan a border or bed of flowers that have good sources of nectar and pollen for the beneficials. Also provide habitat for them.
The border can go along a walkway, at the edge of a lawn, or even instead of a lawn, in or outside of a deer fence. It can be a pretty planting—filled with flowers and grasses, with evergreens that maintain visual structure through the winter.
If you’re having a problem with pests in your vegetable garden mix in some insectary plants to let predatory insects take up residence right alongside the vegetables. See below for ideas.
You can purchase seed blends that are good for an insectary bed. These will help you with the decision-making process. Here are some sources for those: Johnny’s Seeds, Urban Farmer, and Outside Pride to start with. Or, preferably, check with your local nurseries.
But many perennial flowers are perfect for attracting and feeding beneficials, with the benefit of having some cutting flowers to harvest. See some examples in Let Beneficial Insects Work For You in Your Garden.
Make your insectary fire-safe
For those living in high fire-risk areas, keep the highest plants less than three times the height of any low branches above it. Use the more water needy plants in Fire Zone 1 of your landscape. Use lower water need plants in Zone 2 and beyond. (Remember to keep the area from 0-5 ft. out from structures.) Keep out any dead material for fire safety and place it where it can provide habitat for pollinators and predators in a more fire-safe spot.
Create a beetle bank to help with ground pests
Predaceous ground beetles seek out and feed on slugs and snails and their eggs, cutworms, and other soil dwelling pests or pupae. A beetle bank will provide habitat for them. Yes, it’s an earthen bank of beetles.
A beetle bank is a berm or mound a foot above the surrounding ground that’s planted with native bunch grasses. At least three different grass species is best. It’s elevated because these beetles naturally climb to stay dry. The grasses provide a dry, warm habitat for the insects in winter. In spring and summer the beetles will patrol the grounds for snails, slugs, their eggs, and other soil-dwelling pests, and gobble them up.
Beetle banks can add some visual interest to your yard, too. It can be pretty with grasses, but you certainly can add some low-growing plants and other perennials to make a pretty asset to your landscape while keeping pests under control.
Purchase supplemental insects if you need
You can purchase supplemental insects at various stages of their lives. But this is more appropriate for farm operations. And it may not always be effective.
Put insectary plants in your vegetable garden
By interplanting your vegetable garden with good insectary plants you’ll lure in and maintain a beneficial insect population. For example, kale and broccoli are really good at attracting pesky cabbage moths and aphids. But it’s been shown that when the plants are interspersed with helpful flowers, the pest density goes down.
Flowers like sunflowers attract many beneficials in the vegetable garden.
And use herbs like dill, cilantro, basil, oregano, thyme, parsley—all are magnets for beneficials.
The plants in your insectary border and in your beetle bank can be outside of the deer fence and be made of all deer resistant plants.
Plant a hedgerow
A hedgerow is a planting, like a hedge, of mixed plants, especially woody plants, and ideally natives.
Hedgerows include woody plants to provide permanent year-round habitat for predatory insects. They can also provide a variety of flowers over a season for insects, both pollinators and beneficials, and berries for birds.
Hedgerows provide services to orchards and vineyards, and to our homes to block or enhance views, create microclimates that reduce wind speed, protect against soil erosion, filter out air-borne dust.
Consider a hedgerow made of a variety of native plants that are deer resistant, drought tolerant, and even fire safe—so long as they’re planted at appropriate distances.
Know the benefits
With these landscape elements and the plants you can use in them, you’re attracting, feeding, and housing the most helpful insects there are: beneficial insects and pollinators! You’re helping birds, too.
Insects form the base of all terrestrial ecosystems. They feed birds, fish, toads, frogs, snakes, spiders, raccoons, and even bears. They pollinate three quarters of the earth’s plants. Without enough insects, ecosystems will collapse.
So help insects by letting them do the work they naturally do, and be aware of their benefits. You reap those benefits when you help them.
Related Reading:
Let Beneficial Insects Work for You in Your Garden—Here’s All They Need From You
Provide Bee Habitat in Your Landscape: Here’s How
Save our Birds by Planting the Right Plants and Give the best Gift to our Children