So hydrangeas are my favourite plant, but I can't seem to grow them at all. I've now killed four. I've tried in big pots and in the ground (clay, west facing garden) but they shrivel up and die. I've tried giving them loads of water and not watering them and everything in between. I'd love a massive, healthy hydrangea and can grow lots of other stuff. My last remaining hydrangea now has brown leaves with sort of pustules on them (bleurgh). There's no brown on the undersides of the leaves, and some are dry and curled and crispy on the tips. Any ideas?