Calycanthus floridus aka Carolina Allspice

Calycanthus floridus, known as Carolina allspice or sweetshrub, is a deciduous shrub in the family Calycanthaceae. It comes from the eastern United States, from New York and Massachusetts south to Florida and Louisiana. In the wild it grows in shady woods, on moist sites and beside streams. Florida lists it as endangered.

In gardens it forms a dense, rounded shrub 6 to 9 feet (1.8 to 2.7 m) tall. It is often wider than tall, spreading up to 12 feet (3.7 m). Old plants can reach 12 feet (3.7 m) in height. It grows slowly and produces several stems from the base. Root suckers let it spread into colonies. In shade the shape turns loose and leggy.

The leaves are opposite, simple and oval, about 2 to 6 inches long. They are dark green above with paler, hairy undersides and a rough feel. Crushed leaves, stems and bark give off a spicy, camphor-like scent. The leaves turn a modest yellow in autumn. Young twigs are red-brown and mature stems gray-brown.

The flowers open mainly from April to May, with scattered blooms into July. Each one is about 2 inches (5 cm) across and maroon to reddish brown. The petals and sepals look alike, so botanists call them tepals. The scent can suggest strawberry, pineapple or banana, and grows stronger in warm weather. Fragrance varies a lot between seedlings, so buy plants in flower. Butterflies and beetles visit the blooms. Leathery, urn-shaped capsules follow and hang on through winter.

The shrub grows in full sun to fairly deep shade. Sun gives a denser plant, while some afternoon shade helps in hot regions. It prefers moist, rich, well-drained loam but tolerates clay, a range of pH and brief flooding. Dry, sandy ground suits it poorly, and it has little salt tolerance. It is hardy in USDA zones 4 to 9 and rated H4 in the UK. Prune right after flowering, and remove suckers unless you want it to spread.

Gardeners use it as a specimen, screen, informal hedge or foundation plant. It also suits shrub borders, woodland edges and native or pollinator gardens. Plant it near a path or patio to enjoy the scent. The flowers work in cut arrangements. Named cultivars offer white or yellow flowers, compact habits or stronger scent.

The plant has few pest or disease problems, and deer tend to leave it alone. Rabbits, however, like to browse it. Crown gall and powdery mildew can occur, and honey fungus is a rare risk. The seeds contain calycanthine, an alkaloid that can cause convulsions and heart effects. It is harmful to people, pets and grazing livestock. The dried bark has served as a cinnamon substitute, but caution is wise.