24-28" tall x 15-18" wide (seed propagated). This is a delightful new native hybrid wildflower that brings a distinctively cheerful personality to your garden. Blooming in summer, the flower's thin, deep-pink petals curve forward from the center cone like an old-fashioned sunbonnet. A tap-rooted species, this hybrid is a floriferous, rugged performer in soils that are alkaline, well drained (no clay) and of lean-to-moderate fertility. 'Rocky Top' is a good choice for drier growing conditions and rocky, poor soil sites.