Southern Living Garden Book

Absolutely, positively Southern Living Garden Book. I know of no other resource so useful. Gardening in the South is just too different from other parts of the country to depend on Dirr (no offense to him at all). Even though we are the same hardiness zones as the Pacific Northwest, that does not mean we can grow everything successfully here that they can grow there. Be sure to read the first parts carefully that define our southern climate zones, and learn the symbols used thoroughly. This book will not lead you wrong.

I totally agree w/ Southern Living. It is my bible for plants. Here are a few more that are great for Mississippi:
Passalong Plants, F. Rushing
Tough Plants for Southern Gardens, or is it Tough as Nails Plants ?F. Rushing or N. Winter
I think there is another title like "No Fail" also by Rushing or Winter. They are southern plant guru's. If you like roses there is an excellent one with a title like Antique Roses for the South. I don't have these books in front of me, I'm not at home.
Laurie

I like Passalong Plants too!

William C. WElch and Scott Ogden are two excellent writers for the Gulf Coast. Their books are some of my best resources. (But Southern Living Garden Book is still #1.)

Bill Welch and Scott Ogden are both great. Bill has been an extension agent with A&M for years and his roots are in southern gardening. Scott is a walking encyclopedia. Both and any of their books are based on experience.

I did not hear Sally Wasowski mentioned. Her research is extensive as well and I could not garden without her books. While her original focus was Texas natives, she has expanded her research to include both southern and southwest.

My recommendation would be any book by Sally and Andy W.

Mississippi Wildflowers by Jan Midgley.

I have most of the ones you're considering, and most of the others mentioned so far, as well, and if you were getting only one I'd strongly recommend it be Dr. Dirr's massive Manual of Woody Landscape Plants. My copy's in four chunks now from all the thumbing over the years. He's with the University of Georgia in Athens and virtually all entries discuss performance in the South. His other two books mentioned are picture books, lovely to scan but far less extensive.