If it’s the flowers, I wouldn’t worry too much about that this first year. If it’s the leaves, be concerned. It sounds like they got too dry. With newly planted shrubs, it can be hard trying to figure out how much water is the right amount. Especially, with plants going into the ground that are quite large. They are probably losing more moisture out the leaves than they are receiving when watered. Putting the hose at the ground at the base of the plant rather than watering the leaves will help. Our planting and care guide has some good tips on getting plants established.
Thanks for writing!