This week, we’ll be discussing a weeding technique that is less commonly used, but an interesting, safe, and natural alternative to other types of weeding. That is using horticultural vinegar.
Horticultural vinegar is great for organic growers. Unlike household vinegar with contain 5% acetic acid (sometimes 10%), horticultural vinegar contains 20%-50% and has a much stronger smell and stronger properties compared to what you can find for sale at local stores.
To use vinegar, spray directly onto the weeds you want to eliminate. For young plants in the early stages of growth, you should be able to get away with using a weaker strength household solution. For more mature plants at later stages of growth, a higher acetic acid concentration will improve kill rates with contact application.
In our research, we found one horticultural vinegar product in Ontario as a class 4 pesticide. This means it is in the category of a hazardous commercial or restricted pesticides that can continue to be used under an exception to the cosmetic pesticides ban. For most people, you will not be able to purchase or use any pesticide outside of class 5, 6, and 7.
Despite the limitation, you can use household vinegar on young plants and be sure to avoid spraying on any desired plants or on a windy day. Horticultural vinegar works quickly (usually within a few hours) and naturally degrades into the environment without harming pets, animals or other wildlife.
Cover Image by Kate Ter Haar, used under its Creative Commons license.