Most Bugs Are Beneficial in Your Garden

By George Graine, Fairfax Master Gardener
“Pure soft water is the most potent of all insecticides.”
— James Shirley Hibberd in “The Amateur’s Flower Garden” (1884)

So, you are outside totally transfixed while looking at your prize rose bush when you notice a shiny green bug chomping away on the petals. You yell, “Quick, Henry, the Flit!” If you do not remember this really old advertisement, it was the yesteryear bug killer of flies and skeeters. Try doing a computer search as this is an interesting story. Fortunately we have come a long way from this type of treatment for bugs. In years past, having bugs was considered evil or needed to be eradicated by any means available. A fly swatter or butterfly net was not good enough, so the solution was often to kill ‘em all with some pesticide spray. We did not fully appreciate beneficial bugs except for bees and butterflies. These days we know and understand that all bugs serve a purpose. Using the word bug for all types of bug-like creatures is technically incorrect; however, for simplicity let’s leave it that way.

Beneficial Bugs book coverAn interesting factoid is that only one percent of the bug population is harmful. No one knows how many bug species exist on the planet. It could be up to 20 million, and of those only one million have been named. Studies have shown that there is a natural balance happening in the garden where the good bugs are eating the bad ones in order to survive and reproduce. The conundrum, if you can call it that, is to try and balance the ecosystem or as garden writer Jessica Walliser writes, “… in order to sustain a healthy population of predators in the garden, one always has to have prey available.” The problem is creating this balance without inserting ourselves into the natural “battle” that is taking place. In the final analysis of good bug — bad bug in your garden, here is the solution. “… beneficial insects have the ability to learn to see your yard as one where they can successfully find habitat, prey, pollen and nectar –- that is of course if you are willing to make it such a place.” Entomologists claim that only 1 percent of bugs do damage whereas 99 percent are either beneficial or do no harm.

The American Horticultural Society gave Jessica Walliser an award for her book Attracting Beneficial Bugs to Your Garden: A Natural Approach to Pest Control (Timber Press, 2014). Note, too, that this book has a generous section on plant partners and landscape design. You cannot have one without the other to be effective. She has taken the study of bugs to a different and critical level for those who like to garden, especially in a natural way. Her book includes many of the tools and information you need to create a garden to protect and strike a balance for the environment and the gardener. With a superb introduction into the world of beneficial bugs — who they are, how they work and what they eat, Walliser introduces you to the good bugs and the important role they play in your garden. Also noted is an extensive section on predators and parasitoids. By the way, the color photos of these bugs are of excellent quality.

Walliser shows how you can make a bug-friendly garden by planting the “right” flowers and herbs. Her book “… is a guide to selecting, placing and caring for plants that encourage beneficial insects to do damage control on your behalf.” Simply put, if you have a diversity of plants you should have a diversity of insects that will be beautiful, healthy and productive. After realizing the important role that bugs play in the garden, the author provides detailed suggestions for 38 plants that beneficial bugs thrive upon. The selection of plants is in alphabetical order, and many of these plants may be familiar to you, such as coreopsis, aster, Shasta daisy, bee balm and black-eyed Susan. Some are not as familiar including some native plants and herbs. In an interview with Dr. Paula Shrewsbury from University of Maryland Extension, Walliser keys in on the importance of landscape diversity along with the complexity of good bugs. Following the plant suggestions are sections on how to design a garden in order to maximize the beneficial bug population, by creating a garden that will support the nutritional and environmental needs of bug predators and parasitoids.

The last section of the book includes some cautions on the full-service garden center and box store assortment of chemical and organic pesticides. Also be concerned (wary) of advertising about eggs and live bugs for sale. When you read this short section, you may be surprised to find that not all of these products live up to the hype. No doubt you will become a better informed gardener.
Are you up for the challenge, or is it a change?

Recommended Further Reading
Good Bug Bad Bug: Who’s Who, What They Do, and How to Manage Them Organically, 2011, by Jessica Walliser. This book is designed as a practical hands-on field guide for the identification of bugs, whether good (beneficials) or bad (garden pests).

Insects and Gardens: In Pursuit of a Garden Ecology, 2001, by Dr. Eric Grissel. Before he retired, Dr. Grissel was a research entomologist with the Department of Agriculture. Grissel claims that “… a garden is essentially a non-functional ecosystem.” He goes on to say, “… a garden might be thought of as a struggle between a piece of land trying to restore itself to a natural balance and a gardener who hasn’t a clue what that means. Thus begins the eternal battle between the gardener, the garden, and the forces of nature.”

Garden Insects of North America, by Whitney Cranshaw

National Wildlife Federation Field Guide to Insects and Spiders of North America, by Arthur V. Evans