Additive used to increase the pH of the solution, making it less acidic. Adding Dutch Ferti pH+ to your watering solution will slightly increase the potassium levels in the solution. Dutch Ferti pH+ contains 25% potassium hydroxide. This substance is used because potassium is an extremely important element during the entire cycle of a plant’s life. Using potassium hydroxide to increase the pH will therefore most likely not greatly disrupt the plant’s diet, regardless of the phase of the life cycle that it is currently in.