Clematis exist quite nicely in my garden planted at the base of various trees and shrubs. The key is making sure you provide extra moisture and nutrients to the area since the clematis will be competing with the other plants for both of these needed requirements.

Never having grown clematis with passifloras however, I would just keep an eye on the clematis and see if it is being swamped by the passiflora. If the passiflora swamps out the foliage of the clematis so that it can not get enough sunlight, then the clematis will suffer regardless of how much water and nutrients you give it.

THANKS for the info nckvilledudes. I appreciate you taking the time to answer me. :)

No problem jlosc.

I planted a clematis at the base of a lamp post 4 yrs ago. The next autumn, I planted a passionflower (got it on clearance for $2.00) at the same post (but on the opposite side.) I thought the clematis had died.

The following spring (and each spring since then), the clematis flushes out and blooms in April. In May, the passionflower rises from the ground and covers the post. I carefully ensure the clematis receives sunlight.

Each winter, I carefully cut back the passionflower's old growth (making sure to leave the clematis intact.) It takes me about 15 min. to complete. AND we begin the entire cycle anew.

A neighbor was amazed that I had found a vine that "blooms pink in the spring and purple in the summer." lol

Good to know John. If you had planted a type III clematis, both vines could be cut back at the same time and simplify your pruning chores.