Home gardens quickly become “killer gardens’ with heavy applications of chemical-based pesticides and herbicides. Caroline Cox, research director at the Center for Environmental Health, says, “if you add up the use of chemicals which the Environmental Protection Agency says cause cancer, it’s millions of pounds every year.” And U.S. geological surveys have found pesticides in nearly every stream they’ve ever tested. In response, companies have released a slew of natural and organic gardening products that claim to eliminate and prevent pests without harming you, your produce or your dog. But do they work?
The greenest road to a weed-free garden is, of course, pulling them out by hand. But organic sprays leave a minimal impact, too. They’re often infused with vinegar, clove and citric oils—ingredients that naturally combat weeds and unwanted growth. For those who want to eliminate herbicides—but still want to show those weeds who’s boss—there’s the flame weeder, a portable propane tank attached to a tube with an ignition button that torches them where they sprout. But be warned, flame weeders are better for ridding patios and walkways of weeds, and less useful for gardens where you might accidentally destroy delicate plants or good soil organisms.
Wear Out Weeds
While organic sprays and focused flames are more environmentally friendly than their chemical counterparts, they’re not always as effective. According to Joe “Gardener” Lamp’l, host of the new PBS show “Growing a Greener World” and author of The Green Gardener’s Guide (Cool Springs Press), “There’s just not a natural herbicide out there yet that will kill off all your weeds down to the root.” Lamp’l explains that while oil-based herbicides and weed zappers do effectively eliminate the top growth of weeds, they fail to reach the root of the problem—literally.
But such products can make a difference by essentially wearing out the weed. “Every time [the weed] tries to regenerate, it uses some of its energy reserves,” Lamp’l says, “and if you stay on top of it, you can deplete that energy source.” So organic herbicides and weed zappers can be effective—they just need to be applied more frequently, and more generously, than synthetic products. The nonprofit organization Beyond Pesticides recommends that you consult the Organic Materials Review Institute’s (OMRI) complete list of approved organic substances for the best natural weed-killing alternatives.
When it comes to pest control, experts advise gardeners to use a simple physical barrier. A floating rope or a piece of lightweight fabric will safely prevent pests from laying eggs and wreaking havoc on produce. To fend off deer and larger raiders, why not build a fence? For more serious infestations, Lamp’l recommends a simple mixture of soap, water and oils that will stick to the pest and dry out its body. But take note that these soaps will only be effective on younger insects with soft exoskeletons.
Before trying any of these pest-control options, it’s important to locate the source of your problem. “If you just go out there and kill pests, whatever the conditions are that caused pests to thrive are still going to be there,” Cox says.”You need to change the conditions that allow the pests to do well.”
Lamp’l adds that “a healthy garden is the single best pest-control treatment.” Of all the insects in home gardens, Lamp’l says that just 3% are considered pests—the other 97% are either neutral or, better yet, beneficial. That means that many of the creatures in your garden can actually control your pests for you.
So before you start zapping weeds and killing bugs, spend some time getting to know your garden. A healthy garden is well located, diverse and properly maintained, and the more time you put into it, the less likely pests will be a problem.