One of epsom salt’s active ingredients is magnesium sulfate. Magnesium sulfate actually has a neutral pH and won’t change the flower color of hydrangeas. Instead, I recommend using Color Me Pink and Color Me Blue in the spring to change the color. Just follow the directions on the website and label. For fertilizing, use a granular, slow-release product that is high in phosphorous. Phosphorous encourages blooms and Color Me Pink and Color Me Blue changes the color. It’s a perfect combination.
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