I live in Lake Havasu City, AZ and recently purchased a gardenia bush loaded with buds. It is doing well in that it is protected from the wind and afternoon sun. The buds do not seem to be opening up but other buds are setting. I have left it in the pot since I will be leaving in May and I will give it to a full time resident before I leave. Will it bloom? Should I mist it? I give it moisture daily since the temps are in the 80's. The leaves are green and all appears healthy. Does Miracle Grow have the right amount of iron and other ingredients for the gardenia plant? Thank you.
The most likely cause of buds not opening is lack of humidity.
Here are some links to help you with care requirements.