It may be in good soil. If it is, it will leaf like mad.
Lousy soil makes them bloom. Crummy, huh?
It will most likely die back (or be devoured by butterfly larva) and come back next winter. I find that passionflowers either come back or don't and nothing you do will make a difference; they don't live very long. They are by no means annuals, but they will sometimes fail to come back in the spring. And if you have it in a tiny corner count on it taking over that corner and a few more. If you are lucky you will get some of the watermelon like fruit; plant the seeds to continue the line. I have known people to cut these down because they were taking over the yard, so beware.

Some of them bloom best in the fall. Avoid fertilizing them but do water them heavily.

MichaelAT

You know, the Scarlett Passion has never been a great performer in my garden; the main reason is that it is day length sensitive. It seems to only bloom pretty much in short days. In the greenhouse, it will bloom non-stop all winter. Last year we had a very long, non-freezing fall and I had a pretty good show of flowers but still, the frost cut it down when it was just getting good. As for it being hardy...well, sometimes. I have started taking a few cuttings each summer as backups...they root very easily. Usually mine returns each spring but it is slow(!) to get started again. I guess I would say that I treat this plant as a novelty in the garden.
If you like Passion flowers, consider the Blue Passion (Passiflora Cerulea)...it is great, evergreen and makes a good show you can always count on. Look for the white form (Constance Elliot) to mix with it! Blooming togeather, it looks super. I run all my Passion vines togeather...just let them run amok along my chain link fence. Oh, if you want another GREAT one...find "Insence" a amazingly pretty hybrid that also does well in our area. Flowers actually make the Scarlett look...dull. It is also very hardy and suckers quite a bit...share with a friend. I bought a new one (for me) this spring...called Lavender Lady...so far, so good. Making good growth on the fence and blooming on and off all summer. Nice to look at! As to hardiness, well, we will see.

Hairy, my scarlet passion flowers (I've had two) never survived our winters, but they were in the ground. If yours is in a container, maybe you can find a way to cut it back and bring it inside. If that's impossible, perhaps you could take a few cuttings, overwinter them inside, and use them next spring. I wish that I had tried that. They're such beautiful plants!

O.k., so I may to try rooting my passion flower through the winter. How do I do it? Will it root in a vase of water? Should I add some rooting hormone? Or does it root in soil? I never tried rooting a vine before.

I haven't tried it either. Maybe you could do both, and see which works.