By Kristina Valle, Master Gardener
Forget the chemicals, get to know your local insect community! Did you know that there are a number of native insects that can actually help keep the pest population down in your garden? It’s true! There are a number insects that are eager to get to work on the problem pests that are feasting on your plants and flowers. In this article, we will review The Top 5 Beneficial Insects that you should be on the lookout for in your garden, which pests they can help control and ways to attract them to your garden.
Top 5 Beneficial Insects
1. Lady Beetles
Also known as Ladybugs and Ladybird Beetles, these insects are not only fun to spot in your garden, but are extremely helpful in pest control. In the book “The Grouchy Ladybug,” by Eric Carle, you’ll find the Ladybug’s favorite food source on the first and the last page: The Aphid. Aphids seem to show up out of nowhere and can have devastating cosmetic effects on your favorite plants. Enter the Ladybug. Like many insects, the Lady Beetles goes through a large transformation as it reaches adulthood. Many of us recognize the Lady Beetle in its adult form: red with black spots. But if you’ve ever seen an insect like the one below and thought, what on earth is that? You’ve encountered a Lady Beetle in the larval stage.
The larvae eat much, much more than their parents, which is all the more reason to find ways to attract Lady Beetles to your garden. If you can encourage them to lay their eggs among your flowers, their young will be ready to feast as soon as they hatch.
How to attract Lady Beetles
While some people may decide to purchase Lady Beetles online, it’s important to know that they are active insects and just because you release them into your yard, doesn’t guarantee that they will remain in your yard. It is important to provide these insects with an attractive habitat, that will encourage them to remain on the job of hunting pests, laying eggs and overwintering until the next growing season.
Include a variety of shallow flowering plants in your garden. Some of the Lady Beetles favorites include:
- Coriander
- Dill
- Alyssum
- Butterfly Weed
- Yarrow
- Bugleweed
- Cosmos
Shallow bowls of water or moist paper towels will provide the Lady Beetles with a water source.
Encourage Lady Beetles to overwinter in your yard by providing them with an attractive habit. They can often be found in leaf piles, bark, within dead trees or nestled up in ground cover plants.
2. Lacewing
The aptly named Lacewing is a true insect predator, and is most effective at pest management in the larva stage. This insect’s appetite is focused on soft bodied insects like aphids, white flies, thrips and mealybugs. If you turn over a leaf in your garden and locate what looks like hair standing on end, you have located the eggs of a Lacewing.
Once the Lacewings hatch, they get straight to work, hunting and killing as many soft bodied insects as they can find. Unfortunately, this may also include small caterpillars. Notice the jaws on the larvae. These insects can devour up to 200 aphids in a week!
How to attract Lacewings
Like the Lady Beetle, Lacewings can be purchased online and released in your garden. Unlike the Lady Beetle, Lacewings are more likely to remain where they are released.
Lacewings are also attracted to the same shallow flowering plants as the Lady Beetle and will overwinter in leaf piles and debris left on the garden floor.
3. Ground Beetle
As the growing season draws to an end, the Ground Beetle comes to the rescue. This last line of defense is most active during the night, and continues pest management into the fall. You may find them hidden under leaves, rocks or logs. Armed with a strong set of mandibles, this insect’s appetite includes ants, maggots, slugs, caterpillars and aphids.
How to attract Ground Beetles
If you have a garden with ground cover plants, creeping plants or vegetables, you have an attractive environment for a Ground Beetle.
4. Parasitic Wasps
Don’t let their name fool you, they do not sting humans, however, they do sting their prey by injecting their eggs into a host insect. Once injected, the host will carry around the eggs until they hatch, at which point the larvae will consume the host. Common hosts include caterpillars, aphids and woodboring beetles like the emerald ash borer.
How to attract Parasitic Wasps
As long as there is a minimal number of pests in your garden, Parasitic Wasps can thrive. You may find the adults, who prefer pollen and nectar at this life stage, buzzing around the flowers, but even then, they might go unnoticed due to their size (up to ½ inch long). Including a variety of flowers with different bloom times will help keep the interest of Parasitic Wasps.
5. Syrphid Flies
Have you ever heard of hover flies or flower flies? These names are synonymous with Syrphid Flies! Adults strategically lay their eggs near aphids so that when the eggs hatch, they are positioned right near their food source. Larvae can consume between 100 – 400 aphids! Other favorites include slugs and caterpillars. Adults will spend most of their time buzzing from flower top to flower top, enjoying nectar and pollen. Although Syrphid Flies resemble a bee or wasp, they do not sting humans.
How to attract Syrphid Flies
With any beneficial insect, the best way to encourage Syrphid Flies to arrive and thrive in your garden is to have a diverse selection of flowering plants that bloom throughout the growing season. Of all the beneficials insects discussed in this article, the Syrphid Fly is the first to have a favorite color! Although they are attracted to many different flowering plants, they are drawn to white, compound flowers.
A Note of Caution
If you find that your garden’s pest population is out of control and the beneficial insects either can’t keep up or are just the wrong bugs for the job, you may want to explore the application of chemicals. Remember to carefully read the label before using any chemicals for your garden. Not only is it the law, but you want to ensure that you don’t apply a broad insecticide which will kill ALL insects, not just the ones that you’re trying to eradicate. Instead, search for selective insecticides that will not harm any beneficial insects.