Well, I haven't had much experience with transplanting my passifloras, but as far as dealing with scrawny plants, sometimes traumatizing them with digging 'em up and washing the roots off can make them run screaming to the grave.

If I was in your place and wanted to transplant it into a pot on your deck, I'd try to dig up as much dirt around the circumference of the plant as possible (to avoid damaging the roots as much as possible) on a warm and cloudy day I would soak it in a 5 gallon bucket of water to take off the clay, then pot it in some good soil and keep it shaded for awhile until it either looks like it's going to recover and get new growth, or it's going to croak on me. Just don't fertilize it right away, because that will probably really kill it.

Thanks for the tips. I definitely think it will be happier in better soil. Good to know about the fertilizer, because that is something I would have done.

P. caerulea is a tough passie, as passies go. BUT---all passies tend to 'resent' root disturbance. It will probably go dormant and sulk a while, but it probably WILL re-sprout.