You could go either way with your passifloras. The are rampant growers and can easily cover 20'-30' of fence. Keeping them contained will keep the from root suckering which can be a problem in your landscape as well as your neighbors. The weight of a passion vine should not take down a fence, they are more herbaceous than woody. You should be attracting a lot of gulf frittilries and zebra butterflies real soon. Good luck Sue

Not all varieties are rampant growers, either, some being a tad more modest than others. But I normally put mine in the ground, and the gulf frits and zebra longwings keep them in check for me. Your "deep red" one might be Lady Margaret, a great grower with gorgeous blooms. And unlike the scarlet red one, it is not toxic to butterfly larva.

If you have enough room on your fence, I say let them loose and see what happens. It is easy to prune them back if they get out of bounds.

Here's a piccie of Lady Margaret for ya, for comparison:

Marcia

Thanks guys! Yes, Marcia your photo matches my Lady Margaret. I have planted my whitish variety and have been watering it 2X/day. My other 2 plants are still potted and with the lack of rain we've been dealt, I may just keep them that way.
Everyone is very happy with their set up right now and I truly do appreciate you guys writing back with your previous experiences.
I've said it before and I KNOW I'll say it again, there are no better forums than this one.
Thanks,
Sue

Hi
I have a deep red variety that was given to me as a cutting so have no idea which variety. I have completely cut it back 4 times and it is still growing lol. Even thrives on regular roundup sprayings lol.
Much deeper red than the photo . I keep all my vines in buried pots so it's possible to remove . Doesn't work on this type as it still roots where it touches the ground.
Given up on getting rid of it .lol gary