Controlling the pH of the soil or substrate is essential for successful indoor growing. PH is a measure of the acidity or alkalinity of a solution, which affects the availability of nutrients to plants. A pH that is too high or too low can lead to deficiencies or toxicities, and affect crop growth and yield. To measure the pH, there are different measuring instruments, such as test strips, liquid indicators or electronic pH meters. These instruments are available for sale online on our website, where you can also find advice and products to adjust the pH to your needs.