I have the yellow and the purple fruited passionfruit vines. The purple is self pollinating and the yellow needs to be pollinated with another variety (usually Caerulea or the purple edible fruited kind). I just take a little paintbrush and pollinate them by hand. You can also save pollen in a little vial in the refrigerator in case they don't flower at the same time.
My yellow and purple fruited ones like to get quite large before flowering. If you live in a warmer environment it will probably be sooner.
My yellow and purple fruited ones like to get quite large before flowering. If you live in a warmer environment it will probably be sooner.