How to Change the Color of Hydrangea Flowers

Native to Asia, the hydrangea bush, also known as Hydrangea macrophylla, produces round bouquet-like clusters of small flowers. The flowers that emerge in the spring are typically either blue or pink, although there is also a white variety. Blue hydrangea flowers grow in an acidic soil where aluminum is absorbed into the plant through the roots. Pink hydrangea flowers grow in an alkaline soil where there is a lack of aluminum available to the bush. If you wish to change the color of your hydrangea flowers, you must change the soil conditions.

Things You'll Need

• Gallon bucket
• Water
• Tablespoon
• Aluminum sulfate
• Cup measure
• Lime

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Instructions

1. Pink to Blue

   • 1

     Mix a tablespoon of aluminum sulfate, available in garden centers, to a gallon of water.

   • 2

     Apply the mixture around the base of the hydrangea plant.

   • 3

     Repeat this aluminum sulfate treatment several times during the growing season. The hydrangea flowers will become a deeper blue through successive seasons.

   Blue to Pink

   • 4

     Measure a cup of lime, available in garden centers, and set aside.

   • 5

     Water the ground beneath the hydrangea plant.

   • 6

     Sprinkle the lime around the base of the bush.

   • 7

     Repeat this procedure several times a year.