It is hardy in shade in Atlanta.

GGG

It depends on which Australian fern you are referring to.
Dryopteris x australis is a wood fern and will survive in Ga.
Cyathera cooperi is an Australian tree fern and is rated zone 9 and above.
Nephrolepis obliterata is an Australian sword fern and is commonly grown as a house plant. It is rated zone 9-10.
There may be others by this name. That is why it is important to use botanical names.
Try looking up images and see which one you have.

I realize now that I didn't put the correct name. Thanks. I have an Australian Tree Fern. I know that it's zone 9 but just wondered if I could rig it somehow to survive outside planted in the ground and given special treatment.

Australian Tree Fern is hardy in downtown Atlanta in my neighbourhood. It does best here in shade and in a low lying area for protection.

GGG

I have a Sphaeropteris Cooperi (Alsophila A.) tree fern. Will it be OK in moist shade in Stone Mountain, or should I keep it in a pot and move inside in winter? I bought it inexpensively at Home Depot recently.

I made the original post back in '05. I planted the fern in a sheltered location as described in that post. It has survived two winters and looks great every summer. The top dies back during winter and comes back in summer. One winter I made a covering of plastic hoping it would stay green all year but that made no difference. I tried one many years ago in a pot inside but it just isn't moist enough in most homes and I just couldn't keep misting it enough. I'm very satisfied with mine in the ground.