Last year I came across an excellent post on watering in Florida at the very good site “Gardening in Central Florida.”
Michael, the gardener and blogger responsible for the site has given permission for me to link over:
“A commenter asks about watering. There’s a very long answer that I have been articulating in my head for a while that involves various ethical and economical tradeoffs. But the short answer is easy: You need to water as much as the plants need, and more specifically, you probably need to water a lot more than you currently water. Certainly that has been the case for me: Slowly over the past five years I’ve realized a simple and obvious truth: Plants need copious water to grow well here, with our (sometimes) arid climate, strong sun, winds, and overly-drained soils…” (READ REST OF POST)
I have also published Water-Wise Gardening, a fantastic book by Steve Solomon that goes into depth about gardening without much water or irrigation.