Due to nasty weather, I'm going to have to wait one more day before I start digging but it's given me a little more time to think about what I'm going to do once the plants are out. As it seems the pond liner I used is still in good shape and it would be shame to throw it out, I'm thinking I will still use the hole for the plants but instead of being filled with peat, I'll fill the bottom with a couple inches of water and sit the pots in it. I also have a ton of extra aquarium powerheads and pumps so I'll rig something up to help circulate water. Maybe I can finally put my Drosera regia outside too, as it seemed to readily overheat with no moving water around its roots.
I'll get some pics of the project when it's finished. Thanks again for the advice guys!