Sweetshrub (Calycanthus floridus) has many common names, including Carolina allspice, strawberry-bush, sweet bubby, sweet Betsy, and spicebush. As these names indicate, it is valued for the sweet, often fruity fragrance of its flowers. Sweetshrub is native along the east coast from Pennsylvania south to northern Florida and west to Mississippi. In South Carolina, it is native to the Upstate and Central regions. It is hardy in USDA planting zones 4 to 9 and grows well throughout the state.
The native sweetshrub (Calycanthus floridus) blooms in spring.
Barbara H. Smith, ©2023 HGIC, Clemson Extension
Mature Height/Spread
Sweetshrubs grow 6 to 12 feet tall by 6 to 12 feet wide. Plants grown in full sun will be shorter than those grown in part shade. Sweetshrubs have a dense, broad, rounded form in cultivation. They are multi-stemmed shrubs that tend to spread widely by growing new shoots (suckers) along the outer edges of the clump. Wild plants are much more open, tall, and even scraggly.
Growth Rate
Plants grow at a moderate rate of 12 to 18 inches per year under ideal growing conditions of partial shade plus deep, moist, loamy soil. The growth rate will be much slower in dry soil and full sun.
In the fall, the foliage turns to golden-yellow.
Barbara H. Smith 2023 HGIC, Clemson Extension
Ornamental Features
Dark, reddish brown to wine-red flowers open from April to May. They are one to two inches wide, similar in form to magnolia blossoms, and abundant. The first flush of flowers is on old wood (the previous year’s growth). There are occasional scattered flowers on new wood (the current season’s growth) during the summer.
Sweetshrub flowers have a sweet, fruity scent, often described as pineapple, strawberry, melon, banana or bubble gum. The fragrance is most potent when flowers first open and temperatures are warm. The scent varies from plant to plant. Some have little fragrance or even an objectionable odor. To ensure a pleasantly scented plant, either buy while in bloom, propagate by cuttings from a fragrant plant, or purchase a named cultivar known for good fragrance.
The flowers are long-lasting on the shrub and make good cut flowers. They can be dried and added to potpourri. All other plant parts are fragrant, with the leaves, seed pods, and bark having a spicy scent when crushed.
Pollinators such as beetles, flies, and butterflies visit the flowers. Birds use the dense branches for cover and as nesting sites. Deer seldom browse it.
Sweetshrub leaves are relatively large, from 4 to 6 inches long and 2 to 3 inches wide and are arranged oppositely along the stems. During summer, they are a lustrous, dark green and then turn golden-yellow before falling in autumn.
Seed pods are irregularly urn-shaped, 1 to 2 inches long and green, turning brown in fall when mature. There are numerous seeds inside.
The immature sweetshrub seed pod will turn brown when ripe.
Barbara H. Smith 2023 HGIC, Clemson Extension
Ripe seed pods are filled with seeds.
Barbara H. Smith 2023 HGIC, Clemson Extension
Pods often persist throughout the winter and into the following spring. The seeds are poisonous, but only if eaten in large quantities.
Landscape Use
Plant sweetshrub where the fragrance of the flowers can be enjoyed. Choose a planting site along paths, near a bench, next to a patio, or other outdoor living areas. Add it to native plant gardens, woodlands, and shrub borders.
Sweetshrub naturally grows as an understory shrub in mixed deciduous forests, along streams, and in moist woodlands. Although it is easy to grow and adaptable, the ideal growing conditions should be similar to its native habitats. For best results, plant sweetshrub in moist, well-drained, loamy soil, ideally in dappled or part shade. It can tolerate sandy soils and drought with extra care. It is not salt tolerant.
Sweetshrubs are low maintenance. If pruning is needed, do so immediately after flowering to shape or maintain compactness. Cut back branches that cross down to the base of the plant. As suckers emerge, cut them back to ground level to maintain the desired width of the shrub. Dead branches can be removed at any time. For more pruning information, see HGIC 1053, Pruning Shrubs.
Plants can be propagated by seed, but be aware that seedlings may vary in scent and other characteristics from the parent plant. Collect seeds in the fall as the pod color changes from green to brown. Seeds from older pods rarely sprout. Plant the seeds immediately in an outdoor bed or store seeds in a refrigerator for 3 months before planting.
Plants grown from cuttings have the advantage of retaining the features of the parent plant. For best results, take cuttings in July, lightly scrape the cuttings on one side and dip them in a rooting hormone powder. Then, place cuttings in sand or a sandy rooting media. Cultivars vary in how well they root from cuttings.
Rooted suckers can also be detached from the main plant and replanted. Removing and transplanting suckers from parent plants is an easy way to obtain new true-to-form plants. Almost all will root well if adequate moisture is given during establishment.
Problems
Sweetshrubs have no serious insect or disease problems. Phytophthora or Pythium root rots can occur in very poorly drained soil.
Cultivars
The native sweetshrub (Calycanthus floridus) has cultivars selected for flower color and fragrance.
- ‘Athens’ is a selection with greenish-yellow flowers. The flowers are the most fragrant of all the sweetshrub cultivars. Although the flowers are beautiful up close, they do not show well against the foliage from a distance. This plant is ideally appreciated at close range, near a doorway or beside a patio bench. Plants grow to 6 feet tall and wide
- ‘Burgundy Spice’ is a selection of C. floridus var purpureus. It has dark burgundy-purple leaves that keep their color through the hottest parts of the summer. The leaves turn yellow and orange in fall. The blooms are a mahogany color. Plants reach 6 to 8 feet tall and 6 feet wide.
The pale yellow-green flowers of ‘Athens’ (Calycanthus floridus ‘Athens’) sweetshrub are highly fragrant.
Barbara H. Smith, ©2022 HGIC, Clemson Extension
‘Burgundy Spice’ (Calycanthus floridus var purpureus ‘Burgundy Spice’) has deep burgundy-purple foliage.
Barbara H. Smith, ©2022 HGIC, Clemson Extension
- ‘Michael Lindsey’ has dark flowers that are exceptionally fragrant, and the foliage is darker and shinier than the species. Its growth habit is dense and compact, reaching 6 feet tall and wide. The fall color is reliably bright yellow.
- Simply Scentsational® (Calycanthus floridus’ SMNCAF’ USPP 33,550) has very fragrant burgundy blooms on both new and old wood. It was selected for the large number of blooms it produces. Plants reach 6 feet tall and 5 feet wide.
Calycanthus ‘Hartlage Wine’ sweet shrub has 3-inch, slightly fragrant flowers.
Barbara H. Smith, ©2022 HGIC, Clemson Extension
Hybrid Cultivars: Breeders have crossed the native sweetshrub (Calycanthus floridus) with the Asian sweetshrub (Calycanthus chinensis) to create hybrids known as Calycanthus x raulstonii. Other hybrids have parentage of another North American native, the California sweet shrub (Calycanthus occidentalis).
- ‘Aphrodite’ is a hybrid of C. chinensis and C. occidentalis. It has large flowers, 4 inches across. The flowers are deep red and lightly fragrant. The bloom time spans over 6 weeks in spring and early summer. It reaches over 9 feet tall and 12 feet wide and can be pruned to tree form.
- ‘Hartlage Wine’ (C. x raulstonii) has flowers that are 3 inches wide, maroon to wine colored, with wide petals and a light fragrance. It grows larger and more upright than most sweet shrubs, at 8 to 15 feet tall
- ‘Venus’ is a hybrid of C. chinensis, C. floridus and C. occidentalis. It has ivory yellow buds that open to 3-to 4 ½-inches wide, fragrant, white flowers with purple centers. Plants grow 6 to 10 feet tall and wide.
Originally published 02/10
