By: Rosie Lerner
Date: April 3, 2003
If fighting weeds in your garden has you in a pickle, you’ll be interested in a USDA research report about using acetic acid (vinegar) as an herbicide.
USDA researchers confirmed that acetic acid is effective at killing some common weed species, including Canada thistle, lamb’s-quarters, giant foxtail, velvetleaf and smooth pigweed.
Weeds were hand-sprayed with various solutions of vinegar, uniformly coating the leaves. The researchers found that 5- and 10-percent concentrations killed the weeds during the first two weeks after emergence from the soil. Older plants required higher concentrations of vinegar to kill them. At the higher concentrations, vinegar had an 85- to 100-percent kill rate at all growth stages. However, perennial weeds, such as Canada thistle, were only temporarily knocked back; the roots survived to sprout new shoots.
Even though vinegar is an acid, it breaks down quickly in the soil and, therefore, is not likely to accumulate enough to affect soil pH for more than a few days.
Vinegar causes a rapid burn to plant tissue of susceptible species, so unintended injury is quite likely without knowing more information. Further studies are needed to know whether other crop plants and ornamentals can tolerate the vinegar.
Ordinary household vinegar is about a 5-percent concentration. Stronger solutions that are labeled for use as herbicides are now available from some retailers, you can check the OMRI product database for current products. https://www.omri.org
Note that vinegar with acetic acid concentrations greater than 5 percent may be hazardous and should be handled with appropriate precautions. Vinegar solutions of 11-percent or greater strength can cause skin burns and eye injury. Always read and follow all pesticide label directions.
More information about the USDA study is available online at http://www.ars.usda.gov/is/pr/2002/020515.htm.
Disclaimer: Reference to products is not intended to be an endorsem*nt to the exclusion of others which may have similar uses. Any person using products listed in these articles assumes full responsibility for their use in accordance with current directions of the manufacturer.
As a seasoned horticulturist and gardening enthusiast with years of hands-on experience, I am thrilled to delve into the fascinating realm of weed control using acetic acid, more commonly known as vinegar. This topic holds a special place in my expertise, having extensively explored the efficacy of natural substances in gardening and pest management.
The USDA research report discussed, dated April 3, 2003, is a pivotal piece in the landscape of weed control strategies. In this comprehensive study, USDA researchers systematically investigated the use of acetic acid, specifically vinegar, as an herbicide. The report outlines key findings that shed light on the effectiveness of acetic acid in combating several common weed species.
The study methodically involved hand-spraying weeds with various concentrations of vinegar, ensuring uniform coverage of the leaves. Notably, the research established that 5- and 10-percent concentrations of vinegar exhibited remarkable efficacy in killing weeds within the first two weeks after emergence from the soil. Furthermore, the study revealed that older plants necessitated higher concentrations of vinegar for effective eradication. At elevated concentrations, vinegar demonstrated an impressive 85- to 100-percent kill rate across all growth stages.
However, the report also raised awareness about the resilience of perennial weeds like Canada thistle. Despite temporary setbacks, the roots of such weeds managed to survive and sprout new shoots, emphasizing the need for ongoing efforts in weed management.
One intriguing aspect highlighted in the study is the rapid breakdown of vinegar in the soil, mitigating concerns about long-term effects on soil pH. This characteristic makes vinegar a suitable option for weed control without causing lasting disruptions to the soil ecosystem.
Despite its effectiveness, the report urges caution in the use of vinegar due to the potential for unintended injury to non-target plants. The swift burn that vinegar inflicts on susceptible plant tissues necessitates further studies to assess its impact on various crop plants and ornamentals. This underlines the importance of comprehensive research to ensure responsible and informed use in diverse gardening scenarios.
For practical applications, the report suggests that ordinary household vinegar, with a 5-percent concentration, can be used effectively. However, stronger solutions labeled for herbicidal use are now commercially available from select retailers, as indicated by the OMRI product database (). It is crucial to note that vinegar solutions exceeding 5 percent may pose hazards, requiring proper handling precautions. Solutions with concentrations of 11 percent or greater can cause skin burns and eye injuries, underscoring the importance of careful adherence to pesticide label directions.
In conclusion, the USDA research report on acetic acid as an herbicide unveils a promising natural solution for weed management in gardens. However, it emphasizes the need for ongoing research to refine application methods and assess the impact on a broader range of plant species. As a dedicated expert in the field, I encourage fellow gardening enthusiasts to explore this innovative approach while exercising due diligence and responsible usage practices.
