Beneficial Insects in Your Garden: How and Why?
Jun 04, 2018 02:50PM
● By Erica Shames
By Ambrose P. Hill
Throughout the gardening season, many insects inhabit the garden. Some have a negative impact upon our landscapes, while others work to help protect our gardens. It is important to distinguish beneficial insects from destructive ones: beneficial insects control the destructive ones, limiting the need to apply pesticides and other chemicals that harm the environment and our health.
One of the most common beneficial insects found in the landscape is the lady beetle (more commonly known as a ladybug), an omnivorous insect that devours aphids, potato beetle, scale, spider mites, whiteflies and many more. It can be distinguished by its red body with black spots dotted across its back. Within the ladybug’s lifecycle of 4 to 7 weeks, a ladybug can consume up to 5,000 aphids, which breaks down to roughly 50 aphids per hour. Because ladybeetles are omnivorous, they can consume both other insects, as well as pollen and nectar. To attract ladybugs to your garden, install thyme, yarrow, coreopsis and dill. In turn, ladybugs will control insects you don’t want in your garden.
Another beneficial insect that will help to control the problem bugs in your garden is the lacewing. This insect has a green, slender body (approximately half-inch in length) and slightly resembles a katydid. This omnivorous insect will feast upon many pests in your garden, including aphid, potato beetle, scales, spider mites and whitefly. To attract these insects, install plants with high pollen and nectar counts, such as coreopsis, cosmos and yarrow.
In the vegetable garden, the damsel bug is the beneficial bug you want to attract. This bug will help to remove destructive insects from your garden, such as asparagus beetle, cabbage worms, potato beetle, cutworms and whitefly. This insect grows to a length of a quarter-inch, has a brown body and transparent wings. The damsel bug can be attracted to your vegetable garden by placing low growing perennials and vegetables throughout the garden. This bug prefers to stay as close to the soil surface as possible so groundcover plant choices like beans, lavender, creeping phlox and squash vine will help to reduce the population of destructive insects from your garden.
The assassin bug is a prominent beneficial insect living here in North America. Brown and black in color, the assassin bug has a large body with small legs. This beneficial insect will help to rid your landscape of destructive insects, including aphids, cabbage worms, potato beetle, cucumber beetle, earwigs, cutworms, tomato hornworms and Japanese beetle. This bug is carnivorous and prefers gardens with diverse plant material.
One of the smallest beneficial insects in the landscape is the pirate bug, which only reaches eighth of an inch. Don’t let this bug’s small size fool you. This insect can devour up to 30 garden pests during a day, including aphids, spider mites, whiteflies, cutworm and corn earworm. This insect is one of the most common beneficial insects in this area. Coupled with the fact that this insect is one of the first to emerge in early spring, this bug will help to control more pests than any other beneficial insect.
One of the most interesting beneficial insects in the landscape is the hoverfly. Varying in size from quarter- to half-inch, the hoverfly resembles a small hummingbird. Hoverflies are one of the most important pollinators in the garden. In order to reproduce, this insect must have a large supply of nectar and pollen; therefore, it does a good job pollinating many of the flowers in a gardener’s landscape. It is also does an excellent job at controlling destructive insects. This beneficial insect will help to rid your landscape of aphids, cabbage worms, mealybugs and caterpillars. To attract these insects, strategically install plants with high pollen and nectar counts, such as aster, mint, cosmos, daisies, zinnias, statice and sunflower.
Last but not least, we cannot forget the praying mantis. The praying mantis has a long, slender, green body with long slender legs that serve to catch its prey. This insect will feast on almost any insect in the garden, but it is most effective in capturing and devouring potato beetles, asparagus beetles, earwigs and squash bugs. Because praying mantises are carnivorous, they aren’t attracted to plants that have high pollen or nectar counts; however they do tend to prefer to lay their egg sacs upon plants with thicker branches. Japanese red maples, especially weeping varieties, tend to attract praying mantises more so than other plants.
Beneficial insects are vital to controlling pests in the landscape. That is why it is so important to be familiar with common beneficial insects that help to control pests in the garden. In some cases, it is better not to apply insecticide applications to control pests, because in the process we will be killing off the beneficial insects that are attempting to control them. More than likely the pest will eventually come back, but it will take much longer for the beneficial insect populations to build back up in order to control the pest. Therefore, it makes sense to scout out which insects are on your plants before you apply an insecticide application.
Ambrose Hill, owner of Country Garden Landscaping LLC, is a graduate of Pennsylvania College of Technology with an associate’s degree in horticulture. Country Garden Landscaping serves the Susquehanna Valley with landscape maintenance (mulching, edging, weeding, spring and fall cleanup); landscape design; landscape installation; lawncare; and plant healthcare (diagnosing and treating trees and shrubs that are being attacking by insects and diseases). Call Country Garden Landscaping LLC at (570) 648-4057 for a free estimate. Follow us on facebook at countrygardenlandscapingllc. Find us on the web at www.countrygardenlandscapingpa.com.