University of Florida

Changing Hydrangea Color

Hydrangeas that are planted in acidic soils will produce blue flowers, while those planted in alkaline soils will have pink flowers (except cultivars that are genetically bred to be either pink or pure white).

If your hydrangea is producing blue flowers and you want them to be pink, you’ll need to incorporate lime into the soil. To turn pink flowers to blue, use aluminum sulfate. Remember that it may take two or three blooming cycles before the flowers reach the desired color and color intensity.

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