Calycanthus (sweetshrub) is a genus of flowering plants in the family Calycanthaceae, endemic to North America. The genus includes two to four species depending on taxonomic interpretation; two are accepted by the Flora of North America.
They are deciduous shrubs growing to 2-4 m tall. The leaves are opposite, entire, 5-15 cm long and 2-6 cm broad. The flowers are produced in early summer after the leaves, 4-7 cm broad, with numerous spirally-arranged narrow dark red tepals (resembling a small magnolia flower); they are strongly scented. The fruit is an elliptic dry capsule 5-7 cm long, containing numerous seeds.
The bark has a strong camphor smell that is released when stems are scraped. The smell remains strong on twigs that have been stored several years in a dry environment. The scent of the flower has been compared to bubblegum. Calycanthus oil, distilled from the flowers, is an essential oil used in some quality perfumes.
Calycanthus floridus (Carolina Sweetshrub). Pennsylvania and Ohio south to Mississippi and northern Florida.
Calycanthus floridus var. floridus (syn. C. mohrii). Twigs pubescent (hairy).
Calycanthus floridus var. glaucus (syn. C. fertilis). Twigs glabrous (smooth).
Calycanthus occidentalis (California Sweetshrub). California (widespread), Washington (local, Seattle area).