Beneficial insects for your garden

Introducing beneficial insects to the garden is a pet-friendly way to deal with pests without resorting to chemical toxins.

If you share your garden with a dog or cat, avoiding chemical pesticides is a must. These toxic substances can have a devastating effect on your animal’s health and well being, especially if he accidentally ingests them by nibbling the grass or licking his paws or fur after being outside.

This doesn’t mean you have to let your prized roses or tomato plants die if they become infested with pests. In fact, a healthy garden is full of insects, some good and some bad. Usually, nature always seeks a balance by allowing the strongest to survive. You can do the same by encouraging the good guys while discouraging the bad guys. The best way to do this is by providing for a good, healthy soil environment. This means not using any chemicals that will upset the environment and its delicate balancing act. Chemicals not only destroy the insects you don’t want; they also kill natural beneficial bacteria, and provide a breeding ground for harmful bacteria and pests to flourish. Beneficial species act as guardians of the garden, and nothing that will harm them should be used.

There are many sources of biological control products, predators and parasites, such as Peaceful Valley Farm and Garden Supply or ARBICO-Organics.

Whenever using anything that comes bottled or in any sort of container, you must be careful how it is handled and stored, even if it is a natural product. Beneficials require very special handling, and must be released at the right time of year and under the right conditions, so read the instructions carefully to ensure success.
Here are some of many beneficial species that can help ensure a luxuriant garden while keeping you and your four-footed friends safe and healthy.

Semaspore (Nosema locustae)

A naturally occurring protozoan that’s deadly to the grasshoppers and crickets that eat it, but is pest-specific and will not harm anything else. Apply in early spring for best control.

Aphid-lions (Chrysoperia camea and Chrysoperia rufilabris)

Aphid-lions are also known as dobsonflies, ant-lions, or lacewings. The aphid-lion is found in most gardens and is an all-purpose garden predator. The larvae eat aphids, mealybugs, scale, thrips, mites, spider mites and whitefly. They also kill many other destructive insects, as well the eggs of many caterpillars, mites, scale, aphids and mealybugs.

Lady beetle or ladybug

Many varieties are native to North America. Both the young and adult stages eat various soft-bodied insects such as aphids. If a good food source is available, the lady beetles will stay and lay eggs.

Dragonflies and damselflies

The mosquito hawk is another name for the dragonfly, because it devours mosquitoes and other water-born insects. This insect has highly developed eyes, a speedy mode of flight, and is a fierce hunter. The damselfly is the smaller of the two and, unlike the dragonfly, folds its wings on its back.

Fly parasites

This parasite attacks flies before they hatch, by depositing its eggs inside immature fly pupae. The eggs hatch into larvae, which then feed on their hosts.
Praying mantis: The Chinese mantis was first introduced into the United States in 1896. It captures and devours many different bothersome insects, and is very helpful in the vegetable garden.

Spined soldier bug

This bug also preys on many garden pests such as the Mexican bean beetle, cabbage loopers and cabbageworms. Both adults and nymphs attack other pests as well.

Tachinid flies

These prey on a wide variety of insects. They lay their eggs in the host body, which provides the young with a source of food. Compsilura concinnata was imported from Europe to combat the gypsy moth.

Parasitic wasps

Beneficial parasitic wasps (not to be confused with the stinging variety) feed mostly on other insects. Their favorites are caterpillars such as the armyworm. There are many varieties of parasitic wasp. Some attack only certain insects. Encarsia formosa, for example, effectively controls whitefly.

Aphid Wasps (Lysiphlebus testaceipes and Aphidius colemani)

Aphid wasps destroy millions of aphids every year by laying eggs within their bodies. The most obvious sign that these guys are working for your garden are the presence of aphid “mummies” -swollen, dead aphids that are slightly brown in color and serve to protect the developing wasps
Trichogramma minutum and T. pretiosum: These are minute parasites that develop within the eggs of injurious pests such as bollworm, cotton leafworm, various borers, hornworm and codling moth.

Beneficial nematodes

These parasites control the soil-dwelling stages of many insects including borers, grubs, cutworms, oriental beetles, pillbugs, cutworms, fleas, ants, termites and more. You can purchase parasitic nematodes of the Heterorhabditis (Hb) and Steinernema (Sc or Sf) varieties. The Hb variety is most effective against sedentary pests like grubs, and are also good for controlling medfly larvae. The Sc and Sf varieties are used against more mobile pests and are one of the best flea control products available!


This product is made of protein and chitin derived from shellfish waste. It stimulates the soil biota to make enzymes that break down chitin. It’s good for controlling root-knot nematodes: the outer layer of the nematode is made up of chitin so is broken down along with the applied chitin. Clandosan should be tilled into the soil before planting, and then applied every year after that. It can also be used as needed as a side dressing.

Fire ant bait

Contains Spinosad, a product secreted by a bacterium discovered in a surprisingly insect-free Caribbean rum distillery. Fire ants take the bait back to their colony where it is distributed throughout, killing the entire colony within three to 14 days.

Don’t forget our feathered friends

Birds eat many different types of pests. Attracting birds to the garden by providing housing and fresh water will help ensure a good insect balance. Many birds are insect-specific and won’t eat your beneficial bugs.

• One of my favorites is the chickadee. These tiny birds are pest control champions since 90% of their diet is made up of moths, caterpillars, flies, beetles, scale, grape pests, aphids and other troublesome insects.
• Another excellent bird to welcome to your garden is the bluebird; it eats nothing but insects.
• The woodpecker loves the larvae of beetles, ants, borers and many others.
• At night, owls eat many different types of insects.
• Mockingbirds will consume termites, caterpillars and beetles.
• Robins also eat termites, caterpillars and beetles, and they love grubs too.
• The cardinal likes grasshoppers and ants as well as beetles.

Bats consume a tremendous number of insects in their lifetime, and are the best mosquito control imaginable! Protect them whenever you can, and install a bat house to encourage them to take up residence in your garden.

Remember…a healthy, balanced, organic garden will take care of its own pests, and will enrich the lives of both your human and animal family without any need for chemical intervention.