The regular lilies need to get in the ground. Period.
Cannas and Calas can both be dug and stored after they die back. But in your zone, they both should be hardy. The Cannas for sure. (I am not positive on the Cala. - Just checked. Yes hardy in Z 8.) And they will not tolerate a pot for long. Ditto on the Calas - they make a lot of new tubers each year. Both will do much better in the ground rather than a pot.
I agree on the clay. Many folks do ok. I typically do not. And in your area/zone they will dry out very quickly.
