Mary's Hydrangeas

We had these growing up, but we called them snowballs... ours were always just white... maybe there are different varieties...

In any event, Mary says:

I cut back the hydrangea along the side of my house last fall (the gardener did most of the work) and they are healthier now.  This year some are very pink - usually those are all blue. It's all based on the pH level of the soil, although i didn't deliberately change it. There are three separate plants here. Maybe all the bunnies in the neighborhood did something to the soil.