A leopard cannot change his spots, they say, but a geranium can obviously change her hue. Geri has been totally red for the two years we've known her, but decided last week to come out pink. She's seemed a stable soul. Somebody had to put her up to that.
I'm blaming the wren family who built a nest and raised a family in the geranium basket this spring. My theory is their activity altered the soil acidity enough to precipitate a color change. I've switched my own colors for less.