Why pH Balance Matters for Foliar Sprays
You invest time and money into quality foliar fertilizers and pest controls, but if you aren’t checking the pH of your spray water, you might be wasting that investment.
Water’s acidity or alkalinity directly impacts how well plants absorb nutrients and how long pesticides remain effective. If the pH is too high (alkaline), many common inputs degrade rapidly before the plant can use them—a process known as alkaline hydrolysis.
According to the University of Massachusetts Amherst Center for Agriculture, “The pH of the spray solution can affect the solubility of the materials and the rate of uptake by the leaves. Most foliar nutrients are best absorbed at a slightly acidic pH (5.0-6.5).”
A good example is Fe-EDTA (iron chelate), commonly used to treat iron deficiency in roses. Fe-EDTA becomes unstable above pH 6.0, losing its ability to keep iron available to plants. In alkaline water, the iron precipitates out as insoluble iron hydroxide, making the fertilizer useless.
Michigan State University Extension warns that many pesticides breakdown “very rapidly when the spray water pH is greater than 7.0,” significantly reducing their effectiveness.
To ensure your sprays work, bring tap water (which is often alkaline) down to around pH 6.0.
An easy way to manage this without complex meters is using a product like Utkarsh pH OK. It acts as a visual pH indicator, changing the water’s color to show the current level, and contains safe acids to immediately lower the pH to the optimal range.
