Coefficient of Conservatism:
Coefficient of Wetness:
B. S. Walters
A native of China, familiar in cultivation and hardy farther north than other species in the genus. First collected on a beach at Mackinac Island (Mackinac Co.) in 1934 (J. E. Potzger 4611, BUT, ND). Still very rare but to be expected elsewhere as an escape.
This is a shrub with opposite, crenulate-serrate, nearly sessile leaves. The undersides of the leaves and branches of the inflorescence are covered with stellate hairs. The 4-merous flowers are ± purple, with an orange center, in a dense elongate terminal inflorescence, and are very attractive to butterflies.