Description Manutec Hydrangea Blueing Fertiliser is a specific fertiliser developed to maintain safe nutrient level and optimum pH values that are suitable for producing blue hydrangeas. As soil pH determines sepal colour in hydrangeas, it is most important that pH of the soil or potting media is determined and adjusted prior to growing period. Any pH between 5.5 and 6.0 is ideal for Blue Hydrangeas and pH must be acidic during flower bud initiation for petals to be blue. pH can be lowered by adding Manutec Sulphur to the soil or potting mix and maintained by the regular use of Hydrangea Blueing Fertiliser. Follow the directions on the package and apply accordingly.
