Once planted, leave undisturbed. May not bloom for several years after planting. Staking plants before they bloom is a good idea because flower heads are heavy. Plants bloom in late spring. Use balanced fertilizer after bloom.
Foliage is very attractive and resembles a shrub from spring until late fall.
Clumps get bigger each year. No particular growing problems. A wildflower is a plant which is a native American species. Wildflower plantings utilize native species, whether annual, perennial or biennial, from various areas of the country to create a natural-looking garden effect. Wildflowers have to be, since they have to take care of themselves.