What are the requirements for a claim of adverse possession in the state of Florida

7 years. And possession has to be open and notorious.
http://law.findlaw.com/state-laws/adverse-possession/florida/

It would help us help you better if you explain the circumstances rather than ask a technical question.

Scott is correct but keep in mind this does not apply to land owned by the state of any other governmental agency. If you tell all details we can help further

And even if meeting the requirements you have to file in court and the current owner can fight it.