A friend recently told me about an experience she had years ago as a budding, would-be gardener. Creating a pathway through a pretty strip of meadow on her then-rural, Gwinnett County property, she managed to get a nasty case of poison ivy. The next day, armed with pruning shears, she located and cut to the quick every single one of the three-leaved offenders on her property. Only later, when lamenting her sacrificing of the offending plants because of their lovely white blossoms, did she learn that she had exacted her revenge on hundreds of innocent blackberry canes than soon would have borne fruit.
Now, there’s plenty of room for debate about whether any tears should be shed over the loss of wild blackberries on your property, but the story offers a lesson for gardeners worth remembering.
Know your enemy.
This is especially true when dealing with pests in the garden. And it’s the first rule of a practice called Integrated Pest Management, or IPM.
IPM: Know what pests are causing damage so you can
be selective about getting rid of them
The concept behind IPM dates back to the fifties, when entomologists began seeing the damaging environmental impacts of widespread and indiscriminate use of insecticides to control agricultural pests. They realized that the commonly used insecticides of the day were not only dangerous to public health, but also ineffective. The pests were building up resistance to them, and even when primary pests were eradicated, the pests they had previously kept in check were able to flourish and they became the primary pests.
Integrated control, as it was first named, began with development and use of selective insecticides that killed specific pests while conserving their natural enemies in the ecosystem. Further scientific study lead to understanding and promoting other pest control techniques that have moved increasingly further away from the wholesale use of pesticides.
Today, the IPM approach to pest control is aimed at using minimal pesticides, only as a last resort, and even then, using the products that are least toxic to humans and beneficial organisms. It can be applied in the garden and home landscape just as well as on the farm.
Extension services across the country promote and teach IPM principles, which the UGA Extension describes as “A systems-based approach to managing pest populations, which minimizes economic, environmental and public health risks. IPM focuses on incorporating all management strategies (mechanical—including squishing bugs between your fingers—biological, cultural and chemical) in order to maintain pest populations below an economic threshold.” The economic component of IPM is generally most relevant to commercial growers, but we’d all probably agree there’s no point in wasting money on chemicals if you don’t know what you’re trying to get rid of.
My philosophy on pest management:
I’m all in on IPM…And then some!
Let me explain.
It’s a great concept, but IPM isn’t mandated. Growers’ adherence to IPM in the U.S. can be thought of as being on a continuum of chemical use, with homeowners growing some flowers and a few tomato plants at the low end and the largest industrial agriculture operations at the other. The giant food producers are going to care about using pest management practices that minimize environmental and public health risks only to the extent that those practices don’t increase their economic risks—which is never. So they’re still at the very high end.
At the low end of the spectrum are home gardeners, most of whom don’t consider protecting their investments in landscape plants and veggies worth the risk of harming the environment and public health. So they try every pest management tactic they know of before resorting to use of chemicals, if they use chemicals at all, in their landscapes. That’s generally where our clients are.
As for Art of Stone Gardening, we’re so far at the low end of the continuum, that we practically fall off the edge.
You can count the chemical pesticides I use at home and at my clients homes on two fingers—and maybe up to the first knuckle of my pinky.
- In consultation with concerned clients, we will apply the two insecticides, often used in combination, that kill the woolly alegids destroying our endangered hemlock trees. I don’t spray them, so the coverage area is well controlled. We pour a small amount of the chemicals from a measuring cup into several 3-4” holes in the ground, where they’re absorbed into the roots and up into the trunk and crown to kill the insects without otherwise harming the environment. It’s very effective if the tree’s not too far gone.
- In very limited circumstances, we have judiciously applied minimal amounts of an herbicide called glysophate to kill weeds. Applied to plant leaves, the chemical moves from the treated leaves through the plant to the roots, where it kills the weed by disrupting the biochemical process, but doesn’t leech into the soil. Glysophate is an active ingredient in Roundup-brand weedkiller, but if we do use it, we use it in its pure form, which is thought to be less hazardous to the person applying it than in combination with the so-called “inactive” ingredients in the consumer formula.
By the way, I have no worries about whether the chemical is being used safely in the rare cases in which we do use it. Art of Stone holds a pesticide contractor’s license and has a certified pesticide applicator on staff, as required by law. It is me.
Otherwise, we use strictly organic chemicals—the kinds that organic growers would use to limit pests in their crops.
6 tactics for managing garden pests
without using harmful chemicals
Here’s how I generally put it integrated pest management into practice for myself and my clients.
1.Know your enemy.
Identify the problem. Most of the pests and damage around here will fall into these categories, as described by the UGA Extension.
Tattered leaves or flowers can be caused by grasshoppers, caterpillars, adult or immature beetles.
Stippled, bleached or bronzed foliage may be caused by insects like lace bugs or mites.
Die back of plant parts is often caused by beetles or moth larvae.
Evidence of insects themselves, like webs, tents, cases, flocculence (cottony material), frass (fecal material) and sawdust
More times than not, though, if pests are the problem, you can see them right on your plants. Just snap a photo to help you identify what you see. You could be looking at beneficial insects and the damage to your plants could be from something else—like soggy soil conditions.
2.Identify the magnitude of your issues.
Is your pest issue a major problem or a small nuisance? Determining this will help you decide how much time, effort and money you’re willing to throw at it.
3.Learn about your enemy.
Do some research to learn about options for getting rid of the particular pests you have. Learning about their life cycles, habits and mechanisms of doing damage can help you in your conquest.
4.Learn about your friends.
Remember that all bugs aren’t your enemies. In fact, most are your friends. Some “beneficial insects” actually help keep the real pests in check. Identifying your insects will help you keep from killing your friends. You can even purchase beneficial insects to release into your garden.
5.Focus on prevention
Plant pest-resistant varieties of flowers, shrubs and trees, and select the right plants for your conditions.
Keep the plants in your landscape healthy. Pests are attracted to weak and sick plants.
Be careful not to injure trees and shrubs with garden equipment and tools. Wounds attract pests.
Keep beds and other growing areas tidy; pick up pruning debris and destroy any dead plant material.
Try companion planting. Grow plants that repel pests without keeping away pollinators. Learn what will work in your landscape.
6.Decide on a course of action. Or no action!
Based on what you’ve learned about any pests in your garden and landscape, and having taken steps to prevent and discourage pests from settling there in the first place, you can make an informed decision about what course of action to take. If the problem is worrisome enough to you, there are organic products and some natural “pantry” solutions you can try.
Or you can do what I do about pests in my garden. It’s inexpensive, effortless and a hundred percent environmentally friendly.
I do nothing. That’s right. I just appreciate the fact that my plants are part of nature. While nature is beautiful, it’s not without blemishes. So I do my best to keep my plants healthy, but I don’t enjoy them less when they’re not flawless specimens like the ones on the covers of fine gardening magazines.
Caterpillers munch their way through my parsley every year and make it look ugly. But I don’t mind. I know my parsley is feeding what will become beautiful butterflies. So I leave them, and just grow more parsley.
Some of my plants feed rabbits, too. I could build fences around my gardens, or chase the critters away with fists raised in the air. But I don’t bother. As a matter of fact…
…there was a green pepper on this plant this morning.