Manutec Hydrangea Pinking Fertiliser is a specific fertiliser developed to maintain safe nutrient level and optimum pH values that are suitable for producing pink hydrangeas. As the soil pH determines the sepal colour, it is most important that the pH of the soil or potting media is determined and adjusted prior to growing period. Any pH between 5.5 and 6.0 is acceptable during plant growth, but when forcing begins the pH for a crop of pink sepals must be 6.0 or higher. pH can be increased by adding lime to the media and maintained by regular use of this fertiliser solution. Follow the directions on the package and apply accordingly.