Westland Hydrangea Colourant - 500g

Westland Hydrangea Colourant is a salt which changes the colour of pale pink hydrangea varieties to blue and darker pink varieties to mauve blue. However some hydrangeas are bred to be pink in all soil conditions and will not change colour so it is worth checking the plant label. Where the soil is naturally alkaline use ericaceous compost instead or double the application rate.