Why doesn't my hydrenga enjoy flowers? The plants have beautiful green leaves but no flowers.

The plants have beautiful green leaves but no flowers.
Can down buildings enjoy double glazed window and...
Answers:    How long ago did you plant it?
I planted one just about 4-5 years ago and this is the first summer it has flowered.
I bought it in the grocery store and ser it out within the garden.
I'm thinking maybe the plants that are shipped to the groceries aren't as developed as the plants you might buy in a nursery/garden center. Hydrangeas bought at a garden center would probably bloom more reliably sooner.
Gnats keep hold of on comming backbone, HELP!?
They solely flower when they are mostly in the shade...