Vinegar, one of the most common liquids found in household kitchens, seems to be a substance of endless uses. A quick internet search will bring back hundreds of ways vinegar can be used. From hair care to all-purpose cleaner, from medicine to disinfectant, folks are using vinegar for just about everything. So it comes as no surprise that people are using vinegar in their lawns and gardens as a non-toxic alternative to traditional herbicides. Derived from the fermentation process of alcohol, household vinegar is environmentally safe and harmless to humans, pets and wildlife. It’s especially useful where organic certification standards are being practiced.
Vinegar as a Natural Herbicide
While people have been using vinegar as an herbicide for a long time, it’s only been within this century that the scientific evidence of vinegar as a weed-killer has been explored. In 2002, Agricultural Research Service scientists performed tests involving vinegar on some of the most common weeds. They found that vinegar at normal household strength concentrations (around 5 percent) killed the weeds during their first two weeks of life. At higher strength concentrations (around 20 percent) vinegar had an 85 to 100 percent kill rate at all growth stages. Be aware that vinegar with concentrations greater than 5 percent should be handled with care, and solutions greater than 11 percent can cause skin burns and should be applied with protective clothing.
How to Use Vinegar as a Weed-Killer
Any type of vinegar will work as a weed-killer, although white is usually the cheapest. For large patches of weeds, fill up a spray bottle or pump sprayer with undiluted vinegar and apply liberally. This spray method is best for areas such as driveways, sidewalks and other areas where no vegetation is desired. Vinegar is non-selective, meaning it will potentially kill every plant it comes into contact with including lawn grass and other desirable plants. For spot spraying weeds in lawn, use the paint brush method. Take an old brush and “paint” the vinegar on the leaves and stems of the weed you’re trying to eliminate.
Other Tips for Using Vinegar
Gardeners report the most success using vinegar on small, annual weeds with weak root systems. Bigger, perennial weeds may take a few applications before completely dying. For best results, apply on a sunny day with no wind. If it rains within a day or two after applying you’ll need to reapply. While vinegar is an acid, it breaks down quickly in the soil and isn’t likely to affect soil pH levels. Some gardeners claim that adding liquid dishwashing soap at 1 oz. per gallon increases the weed-killing effectiveness of the vinegar.