This is Aristolochia contorta, also known as Dutchmans Pipe, and Pipe Vine. A new stem from this plant starts out as a little purple sprout, then it turns turns green, or even an off white. It likes to wind around things as it grows. Aristolochia contorta blooms from July to August. This plant likes to be in the full sun, but it can tolerate partial shade. Aristolochia contorta is the single food source for the Dragon Swallowtail butterfly, and all Aristolochia, except for the Aristolochia gigantea, are larval host plants for the Pipevine Swallowtail, Polydamas Swallowtail, and Mylotes Cattleheart butterflies. USDA Hardiness Zones 3b to 8