I just planted 5 hydrangea plants 1 week ago. I live in West Michigan and have mostly clay soil. The plants receive sun about 6 hours a day. I've watered them every other day (or we had heavy rain). Today when I got home from work the blooms were mostly gone and the leaves were wilting. This is my first attempt with hydrangeas. Am I not giving them enough water? Should I put mulch around the base? Please help!