If you are set on bearded iris, you might try some of the varieties introduced by Walter Moores from Mississippi. Just type Moores in the Hybridizer box on this page:
http://garden.org/plants/group...
Click "Search" and it will show you all of his irises. His iris are reputed to perform better in the Deep South than most.
You might also consider growing Louisiana Iris, instead. They are better adapted to the climate in that part of the world. They come in an amazing variety of colors and patterns these days.
http://garden.org/plants/searc...