Answer: Buttons and Bows should have white tipped pink petals. These plants are typically cuttings grown rather than grafted onto rootstock so even if your plant froze all the way down to ground level during the winter, it should not have affected the flower color. I wonder if your soil is very alkaline which could intensify the pink color and perhaps diminish the white edges of the petals. Try changing your soil's pH a little by dumping some coffee grounds around the base of the plant (you can do this over a period of weeks or months, until you have accumulated enough to make a 3-4" layer of grounds) or by mixing 1/2 oz (1 Tbsp) aluminum sulfate per gallon of water and apply to your hydrangea every two weeks during the growing season and then again in early spring as the buds begin to swell. Important: Water plants well in advance of application and put solution on cautiously, as too much can burn the roots.
Hope this changes the pH enough to allow your Buttons and Bows to return to its former glory!
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