We have several of these plants that we have aquired during the last two or three years from various friends and, with permission, have dug some up in northern and southern Wood County. I remember seeing different colors in their natural environment, both a reddish color and white, and a very pale pink. In the past these plants have bloomed in a white color, this year, they are all a red color, and one pink one. The plants I separated last fall are again white this year. Can anyone tell me how they change color?
Brady McKinney

I know some plants change color according to the acidity of the soil. I.e., hydrangea bloom blue in acidic soil and pink othewise.

So, I would imagine it is related to the soil pH. Hopefully someone else can tell you for sure.