First off HI and Welcome to the Iris Forum. Hope to see you posting often.

For the clay soil, I can't answer that because I don't have that problem around here.
But for the other questions...
Another question: what kinds of pests do I need to be aware of? Do deer or squirrels eat/dig up the rhizomes? What type of protection should I provide?

I know the deer will eat the leaves of the rhizomes.Not sure what you can do about that, but there are others here that fight the deer and will offer you suggestions. About the squirrels, we have many of them that live in my pecan tree and I have never known them to bother the irises out there. The only thing I have to watch for is voles and the moles. The moles dig the tunnels and then the voles come in and eat the rhizomes. I found that by keeping the mole tunnels closed the voles couldn't do their job. Thank goodness.

Hopefully it's not too late to plant in my zone. Is there anyone in GA or Zone 7 that can offer an opinion?
I am in TN and you should have plenty of time to plant in Zone 7 esp GA. They like to have 6 weeks before the first freeze to get their roots well established.

Hope this helps a little

littlebit

Yes squirrels dig up and chew on rhizomes. They cut the roots off first then eat part of the rhizome. Sometime bad enough to ruin it. I have watched them do it. Squirrels in my city location are starved for food. They also eat my tomatoes. Ever see a tomato 20' up in a tree?
Nothing stops them. They love peanuts in the shell soaked in hot pepper juice. Moth balls does not bother them.

Mike G

Lily:
Maybe Marvin from Ga will see this post and chime in as to planting times, etc. I'll bet you are still OK for planting, but that is just a guess on my part.
As for deer, I know Marvin has a deer problem, but that doesn't mean you will. It all depends if you have deer overpopulation in your neighborhood. Deer prefer other food, but seem to run out of that food in the late winter/very early spring (at least in my neighborhood) and that is when they develop a taste for iris. They will eat the fans but not the rhizomes. Once the woods greens up they 'leave'.
Squirrels will eat rhizomes if there are too many of them to be sustained on their preferred diet. My mom who lives near the beach had tons of baby squirrels one year, and yes, they ate her iris. If you live near woods which have plenty of oak and butternut trees (or other nut trees) the squirrels would much rather eat them instead.
As for sand, this summer I added plenty of sand to my clay soil to combat rot. So far I am pleased with the results, replanted iris are growing back with sturdy increase, but it is still too soon to tell for sure since it has not been very wet here lately.
good luck with your iris, and visit here often, we love to talk about our favorite subject.
Laetitia

I'm in zone 7 NE mississippi. I can plant iris here almost year round. The ground usually does not stay frozen here very long and not very deep. If I plant really late or even in the winter I put a brick over the rhizome to prevent heaving from freezes. I have never had a deer eat iris but they step on them sometimes. Lee Mincy

Well I learned something new today. I guess my squirrels are happy with the food in the area and just leave my irises alone. I have seen them playing in the big bed, but never dining.

littlebit

Thank you to everyone for your help. I'll let you know how everything turns out next spring. I'll be keeping my fingers crossed!!