"Clear Skies" is a tetraploid hybrid of p. caerulea, so the vines and flowers will actually be larger than the already-popular caerulea. It also won't produce fruit unless pollinated by another tetraploid variety--"normal" caerulea won't do it.

As for your questions: the soil shouldn't be an issue. Many passion flowers are adapted to poor soil conditions. I have caerulea, incarnata and Incense planted in my yard, which is heavy black clay, and they are thriving. Good drainage and lots of sunlight are more important. You're right in that they can usually be transplanted without much trauma. Don't be surprised if new plants pop up in the spot you've removed it from, however. Caerulea's one of the passis that will regrow from the roots after hard freezes, so it may well regrow after the removal of the parent plant--it just depends on how extensive a root system it has managed to develop over the past year. Good luck with it!

Thanks. I think I will go ahead an pot it up when I move in a couple of weeks.

The 2 foot vine looks kind of unhealthy. Do these handle being pruned down low well? Or will it do better left alone?

If the vine's only two feet long, then I wouldn't prune very heavily. Maybe 6 inches at the most, and try to keep the roots as intact as possible. You haven't said where it's planted, other than in clay. Is it getting enough sunlight? Is it too damp there/poorly drained? Those are the biggest factors that will set a passi back.

Good luck with it!

It is in a sunny location, but in a spot with poor drainage. Hopefully does better when I relocate it. Thanks for the help.