I have two hydrangeas that bloom pink in my garden. One of them is a Nikko Blue. I understand how the acidity/alkalinity of the soil changes the colors of the blooms from blue to pink.
What I really have been wondering is if there are any hydrangeas that are colorfast, that would bloom whatever color they are going to bloom regardless of the soil pH?
If there are none, why do so many of them have colors in their names?
colorfast?
I think it's only the cultivars of H. macrophylla that change color, so if you get another species of hydrangea then it should stay the color it is (although I think most of them are closer to white anyway). And white H. macrophylla cultivars will stay white rather than changing colors. The ones with colors in their names were probably bred specifically for the quality of that color, in other words Nikko Blue was probably bred to have really gorgeous blue flowers when kept at the right pH, but they didn't pay much attention to whether it would also be a really nice shade of pink if you kept it at a more alkaline pH.
That's interesting, thanks.