Know Your Friends in the Garden

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The days are getting longer and warmer, signaling that spring will be here soon. This is when beneficial insects begin to emerge. Attracting beneficial predatory and parasitic insects into your garden helps reduce the population of unscrupulous insects. Your beneficial insect friends will consume them or use them to house and feed their offspring.

Pollinators are also beneficial insects who spread pollen between flowers which is essential for fruit and seed production. How do I reduce the populations of pest insects such as aphids, whiteflies, scale, mites, mealybugs, thrips, leafhoppers, psyllids, etc. who damage your plants? The average backyard is home to thousands of insects. Only a small fraction of these insects are detrimental. Beneficial insects are the defenders of the garden and we must promote and protect them.

Soldier Beetle

One of the first beneficial insects to emerge is the soldier beetle. The adults are slim-bodied, ½” long, varying in color from red to brown with black, brown, or gray wings. They are important predators in the garden consuming aphids, caterpillars, and other soft-bodied insects. Another beneficial insect that arrives with the onset of spring is the convergent lady beetle (ladybug, ladybird). The larvae resemble a mini alligator with horizontal stripes of orange and black. Both the larvae and adult stage of the lady beetle are voracious eaters. There are many types of ladybugs and other beneficial insects that look like the ladybug. The Vedalia beetle, mealybug destroyer, twice stabbed lady beetle and spider mite destroyer are a few of them.

Spider Mite Destroyer Vedalia Beetle

Not to be forgotten, are the insect parasites. These are parasitic wasps and flies. The larvae of these wasps and flies feed on other insects, or they live inside their host and exterminate them. The leafminer parasite, aphid parasite, and whitefly parasite are a few examples. Some of the best beneficial insects are spiders. Spiders feed on a wide array of insects. Additional beneficial insects are the minute pirate bug, assassin bug, green or brown lacewing, praying mantis, snakefly, damsel bug, and the predaceous ground beetles.

As gardeners, there are many ways to attract and promote populations of beneficial insects. Install plants that attract beneficials in and around your garden, the more, the merrier. These plants will provide them with food and habitat. Another idea is to create a boundary of flowers around your vegetable beds. When the bad bugs enter the boundary, they will be gobbled up by the good guys. Fall and winter beneficial flowers are: Alyssum, Calendula, Candytuft, Chervil, Chamomile, Poppies, Snapdragon, Stock and Sweet Peas. For spring and summer flowers, grow Angelica, Aster, Black-Eyed Susan, Catmint, Coreopsis, Cosmos, Dill, Goldenrod, Marigold, Sunflower, Shasta Daisy, Thyme, and Yarrow.

Consider the impact of non-selective insecticides on your beneficial insect population before you spray the garden to kill something. Non-selective insecticides will kill or have negative effects on a wide variety of insects, good and bad. Another reason not to use these insecticides is it ends up in our waterways. Know what you are spraying for. It might be a good, beneficial bug, not a bad bug. The safest insecticides to use are horticultural oils and soaps, or a blast of water. Many pests can be managed without the use of pesticides. There are a lot of garden centers in our area, that sell beneficial insects in the spring. Bring these friends home, release them in your garden habitat, and enjoy their assistance in the garden.