Smooth blue aster has a very wide range in North America, including Illinois prairies. It can reach a height of 3 feet on unbranched, blue-green stems. The central stem terminates in a panicle of daisy-like, light lavender or light blue-violet flowers that appear in late summer-early fall. The thick, glossy, ovate leaves clasp the stems. It prefers full or partial sun in average, well-drained soil. Provide good air circulation to prevent powdery mildew.