I couldn't help but post my 2 year old hydrangea (bottom picture). I tried to make it turn dark blue to no avail but it did go from pale lavender to lavender-pink. I'm convinced it will never be blue!
The little hydrangea in the top picture is just in it's second season and started out as a little branch which I just stuck in the ground! It isn't even a foot tall and blooms it's little head off! It loves being blue but had no choice since I fed it regularly with "Tru Blue" aluminum sulfate. I think they need to have a tendency to be blue on their own before the aluminum sulfate actually works. Is this called "altered art"???