Natural Cure for Ailing Plants

Home gardeners today are almost more apt to reach for an organic solution to their pest problem as they are for a chemical spray. Our recipe boxes are stuffed with alternative pesticide strategies, and these include everything from basic kitchen ingredients like baking soda and spices to specialty products like beneficial bacteria.

Vinegar has been found to be extremely effective in killing some types of weeds. Scientists credit the acetic acid in vinegar with herbicidal properties. Vinegars made from fermented grapes, apples or grains are all effective.

Vinegar purchased at the supermarket contains approximately 5 percent acetic acid. In field tests, that concentration was strong enough to kill the tops of Canada thistle, though their roots did grow back.

Reports on other species were available, but it wouldn't hurt to try vinegar on different types of weeds in your garden at home. The pH of the soil may drop temporarily due to the effect of the acid, but it should rebound quickly - within 48 hours. And both vinegar and acetic acid biodegrade completely and safely.

Scientists are experimenting with stronger concentrations — up to 30 percent acetic acid — and point out that vinegar products are already registered in Sweden for treating weeds in pavement cracks.

The kitchen spice rack is a potential treasure trove of alternative pesticides. It's long been recognized, for instance, that cinnamon has fungicidal properties. An orchid grower in Iowa lightly sprinkles powered cinnamon on the foliage of diseased plants to treat spots where standing water has rotted the leaves.

One new bio-herbicide on the market contains clove extracts; another is derived from lemon juice and vinegar acids.

It shouldn't come as a surprise that herbs and spices may have useful properties — beyond the obvious, of course. Their tissues contain potent essential oils, many of which botanists haven't even identified yet.

Home gardeners have far outdistanced producers of agricultural crops in their acceptance and implementation of alternative pesticide strategies. In 1973, you were part of the "fringe element" if you practiced IPM (Integrated Pest Management) or gardened organically. In 2003, you're part of the "fringe element" if you don't.

Even back in 1977, the USDA recognized the need to move farmers in the direction of IPM. It adopted a policy that year to develop and encourage the use of IPM in agriculture. In 1993, it renewed that commitment and set a goal of implementing IPM practices on 75 percent of total crop acreage by 2000 to reduce the use of pesticides.

By 1998, in spite of the fact that many farmers were trying IPM, pesticide use had actually increased slightly, as measured in pounds of active ingredients. Researchers noted, however, that use of some of the most toxic pesticides was down, a fact they attributed in part to them being taken off the market.

The search for alternative pesticides continues, in kitchen cupboards and in nature. "E-RASE" is a brand new organic pesticide with multiple properties. The jojoba oil in "E-RASE" acts as an insecticide when directed at whiteflies and as a fungicide when applied to ornamentals and grapes with powdery mildew.

Soybean oil works as well as horticultural oil (a highly refined petroleum product) in controlling spider mites on some plants. And plant leaves aren't as sensitive to soybean oil, reducing the damage to stressed foliage in hot dry weather.