The pH levels (acidic levels) in the soil determine the color of hydrangeas you will have. You can change acidity levels at any time to give a marbled color during growing season. It's kind of cool, really.
Your local plant nursery can help give you tips. It always helps to get local experts talking since the soil in each region is different and may not react the way plant zonings expect.
at 1:24 PM on Mar. 2, 2009