Check with your state's Extension Service. Each county should have it's own Cooperative Extension Office which provides free publications and information for the asking. They can also tell you the average last frost date for your area and ideal planting times for specific crops and varieties in your area.
Just call up the office in your county. Look under the "Government" section (usually blue pages) of your phone book under "Extension". They will have valuable vegetable/gardening tables available specifically for your area from data they've collected from growing those crops in your state.
Florida Extension Service:http://www.ifas.ufl.edu/extension/ces.htm