You say that these are planted on the south side, but they are shaded by some plants. It sounds to me that they are getting too much sun. You haven't really said what is going on with them. You say you wanted them to get established. That usually means the the root system grows while the tops of the plants tend remain about the same. Most hydrangeas do best in morning sun. They like moisture but not wet conditions. Take a look at this site for some helpful info.
If that doesn't help, do get back to us.