A stout, sparingly branched, pubescent perennial, 1 1/2-3 ft. tall, with large, oval, blue-green leaves and showy, spherical clusters of rose-colored flowers. Flowers occur at the top of the stem and on stalks from leaf axils. A grayish, velvety plant with erect leafy stems and with umbels of star-like pinkish flowers in upper axils and at top. Sap milky.
This species is closely related to the Common milkweed, A. syriaca, with which it sometimes hybridizes at the eastern limits of its distribution. These species are similar in appearance and growth form (tall and robust), but can be distinguished by the layer of fine white hairs on A. speciosa and flowers that look like small crowns. Unlike A. syriaca, A. speciosa does not form large clones.