Debbie, thanks for this thread and angie for the tome of info! I had citrus trees in the zone north of here (Gainesville) and they survived the winter of 2010 because they were planted near the concrete and asphalt curb that absorbed heat in daytime.
Frosty Florida sets record low temperatures - USATODAY.com
Soooo, if you plant queens and use rock, you have a better chance they'll survive cold.
Kitty