Can you tell me what this bush is and why it won't flower? It's 10 years old and 8ft by 6ft.
Your bush is an hibiscus cultivar and the maroon flowers aren't fully opening. Correct? Well, you have Hibiscus syriacus "purpureus variegatus". It is primarily grown for its foliage and the flower buds will barely open. There is nothing you can do to change that. sorry