May not bloom for several years after planting. Hairy, toothed leaves appear in late fall, live over into spring. Plants bloom in late spring. Use balanced fertilizer after bloom. Foliage dies down and nothing is seen until foliage begins to grow again in late fall.
Clumps get bigger each year.
No particular growing problems. A long-lived perennial. Grow in full sun. Planting too deeply is a common mistake. Plant at soil surface or just below.