Description from Prairie Moon Nursery: The leaves on Smooth Blue Aster are indeed smooth to the touch. The similar-looking Sky Blue Aster (Symphyotrichum oolentangiense) has rough leaves, as do many other Asters. The tough stem often takes on a shade of blue also and will allow Smooth Blue Aster to stand tall during its long late summer to mid fall bloom. A non-aggressive rhizomatous root system allows the plant to spread slowly. In a garden setting, Smooth Blue Aster will persist for many years.
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