In my practice it is very common for clients to come to me after their homeowners association has issued them a fine or filed a lawsuit against them for completing improvements on their home without approval of the Architectural Review Board ("ARB") or Architectural Review Committee ("ARC").
Often these clients submitted an application to the ARB or ARC and did not receive a response. After waiting a considerable amount of time they then proceeded with the work on their home.
Many associations have a provision in the Declarations or Bylaws stating if approval or denial is not received in thirty (30) or, sometimes, sixty (60) days the application is automatically approved.
If your documents have such language, you will need to be prepared to prove you submitted an application. My recommendation is to send any application by certified mail and be sure to keep a copy of it.
If you are implementing Florida-Friendly Landscaping, please keep in mind you still need to submit an ARB or ARC application. While the Association cannot prohibit FFL, it can go after you for not completing the forms.