Hardy passiflora hybrids

I am new to growing passifloras. Just now I have only a white P. incarnata.
From the internet, I see there are several P. incarnata hybridsd available. Does anyone know how hardy they are, and whether any are fertile?
I am in zone 6, and wild P. incarnata can grow in this zone. I am hoping 3/4 P. incarnata-1/4 other passiflora might survive here. Or even an F2 P. incarnata x other species might segregate for hardines enough to have a few winter survivers here.
Walter Pickett