Pesticide Performance and pH Levels
Water pH is a major component of water quality. Most pesticides prefer pH between 5.5 and 6.5. For some pesticides, such as Malathion, basic pH water (water above a 7 on the pH scale) can interact with the active ingredient and degrade the activity of the active ingredient or even cause the active ingredient to fall out of solution. The same can happen with other pesticides, such as mancozeb if the water is too acidic. The speed and severity at which chemicals break down in water is influenced by the pesticide, water pH, length of time, and water temperature. Some active ingredients can lose more than half of their activity in one hour if they are in the wrong water pH. I’ve developed a chart using many resources to outline which pesticides have problems with certain water pH and the optimum pH for these pesticides.
By optimizing the pH of the water, you can protect the active ingredient leading to greater efficacy in the field. Helping you achieve the desired performance from your spray applications. The pH of your carrier water should ideally be tested during each pesticide application with a hand held pH meter (such as this one which is available from WinField). The optimum procedure is to test the pH as you fill the spray tank with carrier water and then after everything has been put into the spray tank. If you do not possess a pH meter, then you can submit water samples for testing. Most universities and even some local cities will test water at a reasonable price. The reason for regularly testing the pH of the water is because of the variability seen in pH over time.
What do you do if the pH of your carrier water is not right for the pesticide you are using? There are adjuvants that can be added to the spray mixture that lowers the pH of the carrier water in order to get it into the optimum range for most pesticides, between 5.5 and 6.5. WinField carriers two such products that will get the pH into this optimal range, Gulfstream® and Breeze® adjuvants.
When was the last time you checked your water pH? Consider purchasing a pH meter or dusting the one off on the shelf and begin checking your water regularly. The financial and time investment could be the best one you make this year.
The winter months, which hopefully are slower for you, are a good time to review last year. One important item to consider is the performance of the pesticide applications you made.
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