Asclepias syriaca. Common Milkweed prefers dry to wet mesic soils,along with full sun. This plant will grow to a medium height and has a purple summer bloom. Common Milkweed is an essential host plant for monarch caterpillars. This plant has a fragrant nectar that ca attract a variety of pollinators. Common Milkweed pairs well with Big Bluestem, Common Ox-Eye, Showy Tick Trefoil, and Yellow Coneflower.