Q: I have heard vinegar will control weeds, is that true?

 

A: Often you hear of home remedies for almost any malady.  Vinegar has been suggested as an effective herbicide, but until recently it had not been studied for effectiveness.


 

Q: I have heard vinegar will control weeds, is that true?
 
A: Often you hear of home remedies for almost any malady.  Vinegar has been suggested as an effective herbicide, but until recently it had not been studied for effectiveness.
The USDA’s Agricultural Research Service has finally put vinegar to the test. They used concentrations of varying strengths including 5, 10 and 20 percent. Household vinegar is close to a 5 percent solution.  Weeds tested included lambs-quarters, giant foxtail, velvetleaf, smooth pigweed and Canada thistle.
Weeds were hand-sprayed so that the leaves were uniformly coated with material. Young plants within the first two weeks of life were killed with the 5 and 10 percent solution. Higher concentrations provided 85 to 100 percent kill regardless of the size of the weed. Canada thistle proved to be exceptionally susceptible to vinegar. The 5 percent solution gave 100 percent kill of top growth. Note that all weeds tested were annuals but the thistle.
Vinegar is not translocated, so it would burn the top growth of perennials but would be unlikely to kill established plants. Vinegar is commonly made from wine, cider or malt, though a wide variety of materials can be used. This study included only vinegar made from fruits or grains, so it conforms to organic farming standards.
Remember that if using vinegar, it is not selective, so don’t spray over wanted plants.
Oklahoma State University, U. S. Department of Agriculture, state and Local Government’s cooperating.  The Oklahoma Cooperative Extension Service offers its programs to all eligible persons regardless of race, color, national origin, religion, sex, age, disability, or status as a veteran and is an equal opportunity employer.
For more information contact the OSU Extension Center, 14001 Acme Road, corner of MacArthur and Acme Road in Shawnee or 273-7683.