The winter season has settled in and given the Southeast a blast of cold temperatures followed by a warm spell that will bring some timely pesticide applications to our turf over the next month or so. Depending on your location, these applications will vary from nonselective weed control and preemergence herbicides to fungicide applications. When planning these applications, one important question should be considered: What is the pH and hardness of the water that goes in my spray tank? These variables can significantly impact the efficacy of certain pesticides, and testing is crucial to ensure the product benefits your agronomic plan. Here are some key reasons to test the pH and hardness of water used to make spray applications:
1. Pesticide efficacy: Some pesticides are more stable and effective within specific pH ranges. Always read and understand the product label before mixing.
2. Chemical stability: Some products may undergo chemical reactions or degrade more rapidly in water with extreme pH values. Testing the water will allow you to choose products more compatible with your water’s pH.
3. Solubility and tank issues: Testing is vital to determine if the water is suitable for dissolving and distributing the products evenly.
4. Compatibility with adjuvants: Many pesticide formulations include adjuvants that enhance performance. It’s essential to ensure compatibility between these products and your water.
5. Preventing equipment damage: Extreme pH levels can potentially cause damage to spray equipment over time.
6. Cost savings: By testing your water, you can avoid wasting expensive chemicals and fertilizers due to reduced efficacy or chemical reactions.
Now that we know the benefits of testing for potential water quality issues you may be asking yourself, how do I test for pH and hardness? These are your options:
1. pH test strips: These strips contain a unique indicator that changes color based on pH level once the strip is dipped into the water. A chart is provided to determine the pH level. This can be a good way to get a feel for your pH range but is among the least-accurate measuring techniques.
2. pH test kits: These kits contain reagents or tablets that you add to a water sample. The color change of the sample corresponds to a pH level indicated on a chart.
3. pH meter: A more accurate and precise instrument for measuring pH than test strips or kits, these hand-held devices usually give you a quick reading on a digital screen.
4. Send a sample to a laboratory: A lab is usually necessary to determine the exact hardness of water, but they can also give a precise pH value. If you have poor water quality, lab testing at least once a year is recommended.
In summary, testing the water that goes in your spray tank is a proactive measure that ensures the pH and/or hardness is compatible with the pesticides, fertilizers and other products you plan to use. Remember, your final spray tank mixture is usually comprised of somewhere around 90% water and just 10% product. Testing that water helps maximize pesticide efficacy, prevents potential issues, and optimizes the overall effectiveness of your pest control efforts.
Southeast Region Agronomists:
Chris Hartwiger, director, Agronomy – chartwiger@usga.org
Jordan Booth, Ph.D., director, USGA Course Consulting Service – jbooth@usga.org
John Rowland, Ph.D., agronomist – jrowland@usga.org
Chris Neff, agronomist – cneff@usga.org