Posted: 11/03/2015 at 13:32
Containers will not work as even if you are assiduous with watering and feeding it will be top heavy and in the first high winds you will be picking what is left up.
Bamboo can get that tall quickly, if you buy mature specimens.
Some native trees grow fast - Rowan for example but are bare in winter.
Laurel or Leylandii do come to mind as evergreen screening plants but will still take some time to grow 9ft.
You can make raised beds to give an extra 2-3 ft.