Clump-forming perennial, covered with branched flower panicles that hover over the foliage like a cloud late summer to fall.  Provides both food and shelter for songbirds. Best in full sun, dry to moist soils. It's worth noting that the seedlings often differ significantly from the original plants. 
 
Easily started from seed; can also be direct sown outside in moist soil. Cold, moist stratification before sowing may help germination.