Application - Change hydrangea flower colour to pink; maintain pink flower colour, raise soil pH and make soil sweeter (more alkaline).
Rate - Mix 25ml to 5L water, ensure all the measured liquid is washed into the final mix.
Frequency - Every 3-4 weeks.
Timing - Apply any time of the year or after winter pruning to adjust and maintain flower colour.
Area - 5L/5m2: apply to moist soil around plant.
For best results, check the soil pH before and during treatment: (at least every 3 months) the optimum soil pH to ensure pink flowers is 7.5 - 8.5. Do not raise soil pH above this range as it could lead to plant damage. It is best to apply many smaller treatments rather than a single large treatment. To raise the pH of highly acidic soil will require a large number of repeat applications.