Doff® Hydrangea Colourant can change pink hydrangea flowers to a mauve/blue by making the soil more acidic. This process can take a few weeks and may also need application in the current season to produce the change for next season. The powder contains aluminium sulphate which can either be mixed into the soil or diluted with in a watering can.
Hydrangea flower colour changer
For outdoor or pot container Hydrangeas
Changes the flowers from pink to blue and with regular application keeps the colour change all season long.
Mix in soil or dilute in watering can
Convenient 250g bottle