2018 ASHS Annual Conference

Horticulture producers, as well as home gardeners, constantly ask about an economic at the same time effective substitute to expensive herbicides that can be used in organic production systems. A specific interest is in a cost-effective alternative to the herbicidal product, such as Axxe, an OMRI listed broad-spectrum herbicide that controls grasses and broadleaf weeds. The key ingredient in this herbicidal soap is a form of ammoniated pelargonic salts. They work by burning plant foliage that is contacted by the product. Lately, a great deal of interest has been conveyed in the use of acetic acid, commonly known as vinegar, as a broad-spectrum herbicide. While many subjective reports of the effectiveness of vinegar have been available, research to substantiate these claims is inadequate. The current study evaluated the herbicidal effectiveness of acetic acid when used as a diluent for the herbicide product Axxe, for row-middle weed management in organic plasticulture systems. The experiment was conducted in an herb (Rosemary), under organic production. When the standard use rate of herbicide Axxe was diluted to half rate with vinegar (5% acetic acid), the control of broad-leaved weeds and grasses was equivalent to the full use rate of Axxe. This study showed that acetic acid could be a viable and cost-effective diluent for herbicides like Axxe, from an economic perspective of broad-spectrum weed control in organic production.