This is definitely a passion flower. Depending on your location, you want to remove this from the ground. While a beautiful specimen, its extremely invasive and you probably have it due to a neighbor’s neglect. Speaking from experience, I planted this in a stone garden. It spread from my house, under the street and across to my neighbors house on either side of me (approximately 50 feet and more). 🙁 I can tell you that it was more vigorous the next spring after a winter. I moved before they could chastise me… (not because of the plant though).

Thanks, hortiphoto. I didn’t realize there was more than one type with white petals. That’s what I get for using Google images!

Passiflora incarnata typically has greenish cream styles and stigmas while those of Passiflora caerulea are purplish red, as seen in the photo above.

Passion Flower (Passiflora incarnata).

That’s the blue passionflower (Passiflora caerulea). Regrettably, in some places it’s anything but rare and can be very invasive. Next to the banana passionfruit (Passiflora mollissima) it’s probably the most rampant species in the genus and also the hardiest. You can see pictures of both species at http://www.botanicalstockphotos.com/photos-passiflora-33.htm .