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The colorful assassin bug nymph is a valuable predator insect.

I have this vision of an ideal garden: It rains twice a week in summer — including July and August — so I don’t have to water, with a perfect balance of predator and prey, and no diseases, with woodchucks, rabbits and other wildlife skipping merrily through the garden looking cute and interesting without doing any harm. Ha.

But reality bites when a midsummer inspection tour of the garden reveals dogwoods that sport a dusting of powdery mildew, lacey hosta leaves and black spot on roses. Gardening mostly chemical free at Chaos has made a real difference. Sure, there are holes in a few plants — insect pests do have to eat, after all. But predators are everywhere here. No insecticides means plants and insects aren’t poisoned, so the chain of life goes on as it should. Spiders dine on healthy insects, praying mantises and assassin bugs eat spiders and pretty much everything else. Bees, wasps and flies are predators and prey as well as pollinators. Lightning bug larvae eat whatever is in the ground with them; dragonflies and carnivorous beetles take care of a lot of everything else.

In turn, songbirds eat all the above; box turtles prowl for slugs; hawks and owls eat voles, mice, frogs, snakes, smaller birds, small mammals and reptiles that also eat insects. Snakes lunch on eggs of birds that would eat them, small mammals and even each other. Then when anything dies, insects are clean-up crews, keeping the circle of life going round again.

Chemicals and poisons hurt them all and disrupt the marvelously efficient ways of doing things that nature has developed over eons of trial and error. Sometimes, weather or a chaotic incident upsets a part of the balance, and we get swarms of insects that do us no good or an insect introduced from another part of the world becomes a problem. Our first instinct is to panic and reach for a bottle of poison to kill the intruders, but that usually proves to be a short-term fix, causing more problems than it solves; eliminating bugs, predators, pollinators and all; even harming birds and mammals — and ultimately us as well as we end up with the poisons in our own bloodstreams.

Sometimes the best solution is to just wait out an invasion because it most likely won’t recur for years, like the swarms of armyworm moths that hit a few years ago, or coreopsis beetles that wiped out a whole season’s plants this spring much to the dismay of my dedicated earth steward son-in-law.

Working with the natural rhythm of things can be critical, like waiting to plant squash until the bugs that would eat it have completed their cycle and gone, or pulling a small population of bagworms off junipers before they become a huge infestation.

We have plenty of alternatives to that bottle or shaker of Sevin dust, too:

A drop of mineral oil on corn silk prevents corn ear worm eggs from hatching. Picking potato beetle larvae off potato plants and dropping them into a coffee can full of soapy water and kerosene like our grandparents used to do (or pushed that job off on us kids) works wonders.  

As for aphids, a strong stream of water from a hose knocks them off plants, killing a lot of them, and survivors can’t get back once they are down. Ants farm them, so you may have to repeat that treatment a few times.

Floating row covers prevent those pretty white cabbage butterflies from laying eggs on brassica crops in the first place. Crop rotation and destroying badly-infested plants disrupt life cycles of caterpillars and eggs. Some determined organic gardeners resort to drastic means: I once watched my daughter spend an afternoon with her Rainbow vacuum sucking cabbage worms off her kale.

Bacillus thuringiensis has been touted as an organic caterpillar control for years, but it kills all caterpillars — even butterfly and moth caterpillars we want to protect. Recent research shows that it too may have long-lasting toxic effects, so I think I’ll skip that until we know, as Paul Harvey used to say, the rest of the story. I’ll use a drop or two of vegetable oil in birdbaths instead of mosquito dunks for mosquito prevention.

Companion planting can help too. Dill is said to repel cabbage butterflies. Planting French or Mexican marigolds around a garden repels other insects, but powerful chemicals they produce could be a growth inhibitor for certain herbs. A good book on companion planting is a valuable guide.

Then there are fungi and diseases. Powdery mildew on a variety of plants — phlox, zinnias, monardas, roses, many vegetables, rust and black spot on roses — are all part of living with the humidity of the Ozarks.

 While powdery mildew hasn’t hurt our dogwoods in the long run, it can kill some plants, especially garden veggies. Good air circulation is a key to prevention. Many different organic formulas are out there, most also effective against black spot and rust. Some recipes call for hydrogen peroxide, skim milk and baking soda, along with horticultural or vegetable oils and/or insecticidal or Murphy’s oil soap. Oils and soap smother insects and spider mites, and baking soda creates an alkaline environment in which fungi cannot live.

A fungus fact: powdery mildew on one type of plant is not the same as powdery mildew on another and won’t spread, for example, from roses to squash.

I have heard it said that for every natural problem on this planet, including human diseases, there is a natural cure. If we open our eyes and minds, nature will teach us how to find them.

Sandy and Jim Parrill garden at Chaos, their acre of the Ozarks in Joplin. Sandy is been a lifelong gardener and a Missouri master gardener. Jim is a former garden center owner and landscaper, and both are past members of the Missouri Landscape and Nursery Association. Email them at

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