I planted 5 little lime hydrangeas in June. They were doing fine, until about a month ago and 1 turned brown. Monday another one turned brown and last night another one. The leaves are still on them and they were blooming. I am afraid I am going to lose them. I water every 3 days from the ground. Have I overwatered? I cannot find anything wrong. Do I need to dig them up and replant with fresh soil? This is my initial reaction. I have never experienced this. We are in a drought in my county.