Temperature and rainfall affect the intensity of leaching and the weathering of soil minerals. In warm, humid environments, soil pH decreases over time through acidification due to leaching from high amounts of rainfall. In dry environments where weathering and leaching are less intense, soil pH may be neutral or alkaline.

Gypsum (Calcium Sulphate, CaSO4.2H2O) is a sedimentary mineral. It is very important for the treatment of alkaline soil.

It’s important to grasp that bicarbonate levels in your irrigation water—its hardness or softness—affects your growing media and crops. Bicarbonate level is also measured as alkalinity. Hard water has a high bicarbonate level and high alkalinity. Soft water has low amounts of dissolved bicarbonates and low alkalinity. With a hard water supply at your growing operation, the bicarbonates can react and make your growing media pH more alkaline over time. The extent and rate of change depends on how hard your water is and the volume of hard water applied to the crop.

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