To the veterans of this group, I know this is going to sound like a dumb question, but how do passiflora climb? By tendrils? By wrapping themselves around a thin support? Do they need to be tied or will they anchor themselves without help?......Every pic I see is so lush with foliage that I can't see how the vines actually support themselves. (As you can tell, I'm a newbie to passiflora!!).......I have a few 3" seedlings and am not sure what kind of vertical support they'll need as they grow.....Many thanks!