The best pH and EC will depend on the type of orchid you are growing as well as the fertiliser regime you use. We provide Orchiata at a start pH of 5.5 – 6.5 through the addition of dolomite. From research, most orchids grow well within this range. The initial EC of Orchiata is < 0.3 mS/cm, however, with fertiliser addition this will slowly increase. Over time the pH will eventually drop and the EC will increase. It is important to check the pH and EC to make sure a balance is maintained and plant management in the pot is correct.