Breaking Free From Pesticides

We are advised to stop to smell the roses occasionally. But along with the perfume comes a whiff of pesticide. Most of us want to get away from pesticides and herbicides. Is it possible? Where do we start? It begins with a change of heart. The reluctance to bring out the pest-killing sprays takes hold when a gardener embraces the philosophy of a naturalist. And with that comes the abolition of poisons.

It’s good for wildlife to be pesticide free; it’s good for gardeners, too. We have labored for years with toxins we do not understand or use wisely. There’s much to be gained by avoiding poisons and little to be lost. We do have to think differently by understanding the way nature intends plants to grow and flourish.

Nature rewards diversity. There's good reason for this evolutionary development. If one species of plant is wiped out by a predator, other species may prevail. Most insect pests are specialists that attack a particular kind of plant: the morning glory family or the cabbage family. The cucumber beetle may attack the entire squash family but leave all else alone. Of course there are a few pests like grasshoppers or European earwigs that cross plant families regularly, but diversity may dampen the chewing of these insects, too. They will be drawn to what they like best and leave less tender tidbits alone.

We’ve forgotten this essential piece of wisdom when we plant only one kind of grass, one kind of rose, one kind of tree. It’s easy to be wiped out when all of our landscaping relies upon a few plants.

Every corner of the world offers a certain kind of weather, soil, water and insect population. Finding the appropriate plants for your corner of the world is key. In my garden the soil is alkaline, the water is precious and the temperature changes are extreme. I must choose trees that flourish in alkaline soil, can take meager watering and survive a 50-degree drop from a warm winter day to a frigid night. The tree list is short. It includes a few native conifers and some adaptable trees from other parts of the world.

Aside from the tree list, grasses and perennial flowering plants fill the bulk of my garden. I can grow penstemons and ornamental grasses that might rot in other moist climates. My palette is filled with highly textured leaves in soft sage greens or waxy sedums. Sages and thymes flourish and I rely on a few drought-tolerant shrubs that make their homes in my part of the world. The Front Range of Colorado is a natural shrub land and I mimic that landscape.

Not every native Colorado plant will grow in my garden. Only a few take hold with vigor. But of those few, all are indestructible. Nature provides them with their own toxins to ward off predators. They nestle into my soil, ask for little or no water and withstand wind, snow, blistering heat and aridity. Far tougher than I am in the garden, they need little care and reward me with spring blossoms, fall berries, stunning foliage and food for insects and birds.

If you hang a bird feeder of any kind outside: seeds, sugar water or tallow--consider that insects are the most important food source for many birds. Hummingbirds need tiny insects for protein as much as they require nectar. Many birds are poisoned by toxins poured onto seed heads, sprayed onto tree limbs or pesticides that drift into birdbaths. Benign insects need other insects for food, too. Ladybugs need aphids and many native wasps require caterpillars. Robins feast on worms. However you look at the pests in your garden, they are fodder for another creature. If we desire birds at our birdbaths and feeders, we have to banish the poisons that kill them.

Those of us who have labored in the vegetable garden know that prevention is, indeed, worth a pound of cure. Spreading row cover over any young broccoli transplants prevents the cabbage moth from laying eggs on our cauliflowers and cabbages. Getting rid of the cabbage maggots after the eggs have been laid is a study in despair. Some simple but effective barriers trump any amount of picking off insects, spraying with a hot pepper spray or washing the plants with a soap solution.

Here is one example: putting out eggplants when they are much larger than conventional gardening lore suggests helps to alleviate any infestation of the flea beetle. True, the beetles will arrive and attack the plant, giving evidence by their tiny shotgun holes. But a larger plant will often sail through the onslaught where a tinier specimen will crumple and die. The beetles won’t last long and their chewing episode will fade into the past.

Tomato cutworm collars protect young transplants from being destroyed by underground grubs. A simple strip of cardboard rolled into a circle around the base of the plant prevents the cutworm from curling and chewing the stem. Push the cardboard collar just two inches into the soil. Eventually the collar will disintegrate into the garden soil but not before the cutworms have changed into another stage of growth and moved on. 

If a plant is constantly attacked by pests, it’s worthwhile trying to figure out why. Most plants produce a kind of toxin to discourage pests. Ponderosa pines produce a toxin that makes their needles poisonous to nearly every creature except the Abert’s squirrel. This squirrel does little damage to the tree and has adapted to absorb and nullify the toxin. But when the pine declines, due to drought or other disasters, it fails to produce the toxin. That allows pests to take a foothold.

If your plants are constantly under stress, they, too, may not be able to fend off invaders. Perhaps there is a mismatch of soil, too much or too little water, or climate stress undermining your landscape. Zero in on the problem and you may be able to solve it. Kentucky bluegrass tries to grow in midsummer but generally succumbs to the stresses of heat. Cut back on the vast expanse of grass, especially next to high heat areas of sidewalks and driveways. It will never look good in July, but it won't be quite as stricken if it's sheltered.