Produce and deepen blue coloured hydrangeas with this rapid action, blueing tonic. The Yates Hydrangea Blueing Liquid Aluminium Sulfate is an easy to use liquid formulation that supplies aluminium to your flowers, which produces an intense blue.
Keep in mind that soil PH affects the colour of hydrangea flowers.
- Acidic soil (pH 4.5 - 5.5) will produce blue flowers.
- Less acidic soil (pH 5.5 - 7) will produce pale, purplish flowers.
- Alkaline soil (pH 7 - 8.5) will turn flowers pink. You can make your soil more acidic with Yates Soil Acidifier.