Vinegar is an acidic solution that removes the waxy coating on a plant's foliage, leaving it vulnerable to drying out. Low concentrations of vinegar burn only the foliage, leaving the roots alone to regenerate when possible. Stronger concentrations can burn the plant all the way to the roots.
Spraying vinegar on weeds can be an effective means of removal. However, vinegar is not selective in the plants it destroys. Over spraying can kill surrounding vegetation, leaving undesirable brown patches in lawns and destroying garden plants.
Common household vinegar contains approximately 5 percent acetic acid. Horticultural vinegar contains 20 to 25 percent acetic acid. This increased acidity allows the user to spray horticultural vinegar on plants without fear of plant foliage growing back. Care must be taken to prevent contact with the skin and eyes.
Spraying vinegar on the soil is another organic method used for killing undesirable plants. Soils with high vinegar concentrations have a pH level that is too low for plants to take root. Adjusting the pH level of the soil with vinegar effectively rids an area of vegetation. Before adding new plantings, lime must be amended to the soil to neutralize the effects of the vinegar and bring the pH levels up.