These blooms in two shades are growing on the same plant. That seemed unusual to me. I know the color of hydrangeas is determined by the acidity of the soil. I wonder if that is the case here.
It's very pretty. Maybe this plant knows that "variety is the spice of life" (o: It's possible that not only the accidity determines the color, but the pollination as well. Perhaps different bees are the cause here. I don't know, I suppose a biologist or expert gardener might know for sure.