Controlling the pH in the root zone is even more important. In some test we have seen that the available pH equipment didn’t give always the same result. Even when we have calibrate the equipment we still saw a difference up to 0,5 pH. For this reason I advice you to keep the pH in the root zone below 6,5. (best is between 5,5 and 6,0) But what can we do if the pH is to high? For this you can follow the steps below. 1) Check the pH from the dripper and make sure the pH is between 5,2 and 5,7 2) Give (if possible) more water to flush out the high pH 3) Add extra ammonium (Haifa MAP) (be careful !) What are the problems if the pH is to high: 1) Plants uptake of the trace elements Iron (Fe) and Manganese (Mn) is problematic 2) Plant uptake of the element phosphate (P) is problematic 3) Phosphate (P) become deposit with Calcium (Ca) and Magnesium (Mg) what can block your drippers Even when you have automatic pH control on your fertilization system control minimum twice a week the pH in the root zone and from the dripper just to be sure!