Water hardness refers to the concentration of dissolved minerals, primarily calcium and magnesium, in source water.
When using fertilizers, it's important to consider your water's hardness level. Water with an electrical conductivity (EC) between 0 and 0.3 is generally suitable for use without modifications.
However, if your water has an EC of 0.4 or higher, it's advisable to have it analyzed for calcium, magnesium, sodium, and carbonates.
High levels of magnesium and calcium in water can impact fertilizer compatibility and nutrient availability.
To accommodate hard water, you may need to adjust the ratios of your 3-part fertilizer, dilute the water with reverse osmosis (RO) water, or add acids to optimize the pH level.