This is Asclepias exaltata, also known as Poke Milkweed, and Tall Milkweed. This is a great wildlife plant because it supports several different bees, butterflies and birds, especially hummingbirds. This plant likes to live in the full sun where it sports violet and lavender blossoms from the middle of the Summer until early Fall. Asclepias exaltata is a nectar source for the Spotted Thyris butterfly. Asclepias in general are documented nectar sources for the Monarch, Orange-edged Roadside-Skipper, Dina Yellow, Carus Skipper, Eastern Tiger Swallowtail, and Falcate Metalmark butterflies. It is also the nectar source for the Clarks sphinx, and Milkweed Tussock moths. USDA Hardiness Zones 3 to 7.