Hydrangea color and soil pH

[gardengrower3]

I have a great pink hydrangea in my garden that I would love to be blue. I heard that if you lower the soil ph it helps hydrangeas turn blue. Is this true? How fast will it happen? How do I go about this?

Thanks!

[Perennialnorthernmichigan]

Use aluminum sulfate once in the spring.Go ahead and do now. Also Hydrangeas love to be fertilized, A 10-7-7 rhododendrum feed will help achieve a very blue color. The fertilizer probably twice in a growing season. Have fun with your blue hydrangea!
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