MistaOCanswered grow question 6mo ago If your pH level is correct and you can confidently rule out an issue with the pH of your watering solution, then itās most likely a case of over-fertilization. In that situation, the right approach is to water with pH-adjusted water only for a while. Personally, I always water at a pH of 6.2 ā a range between 6.0 and 6.5 is perfectly fine for soil.