Chimonanthus

A genus of 6 species of shrub related to the Calycanthus all of which are native to China. They typically leaf out early in spring and can be either deciduous or evergreen depending on species.
Easy to grow, they prefer full sun on fertile well drained soil. Insect pests and disease problems are rare. Propagation is typically from softwood cuttings taken in summer.
Seed can be sown as soon as ripe and grown in pots in a position protected from winter frosts however seed grown plants can take up to 5 to 10 years to bloom.
Plants growing at northerly limits of hardiness benefit greatly from shelter from winter winds and protection from late spring frosts if in areas that they occur.

Chimonanthus nitens
A large, semi-evergreen to evergreen shrub native to southeastern China. Some records include: fastest recorded growth rate - 7.5 feet; largest on record - 20 x 13 feet.
The oppositely arranged, smooth edged, elliptical leaves are up to 7 x 3.5 inches.
The foliage is glossy deep green.
The attractive, slightly fragrant, star-like, solitary, creamy-yellow flowers, up to 0.3 inches wide, are borne during autumn.
Hardy zones 6 to 9 in sun or shade. An excellent shrub for screening.

* photo taken on April 11 2010 @ U.S. National Arboretum


Chimonanthus praecox ( Wintersweet )
A very vigorous, erect, bushy deciduous, large shrub to small tree, reaching up to 12 feet or more, that is native to most of southern China. Some records include: fastest recorded growth rate - 6 feet; 20 years - 20 x 15 feet; largest on record - 20 x 25 feet.
The rough-textured, lance-shaped leaves are up to 9 x 3.5 inches in size. The inch wide very fragrant, translucent yellow flowers with a red basal spot are borne on second year wood in late winter before the foliage emerges.
Hardy zones 5 to 10 in partial shade on deep, light, well drained, acidic soil. The Wintersweet prefers hot summer climates such as the Mid Atlantic and Deep South U.S. In cooler parts of its range it blooms best against a warm south facing wall.
Rarely requires pruning however it is versatile and can be trained as a tree or cut to within a foot from the ground in late winter to rejuvenate if needed.
Can also be pruned severely immediately after blooming to increase vigor.
It may be prone to aphids in some gardens.

* photo taken on May 1 2010 @ U.S. National Arboretum, D.C.

* photos taken on May 8 2010 @ U.S. National Arboretum, D.C.


* photo taken on May 6 2010 @ Brookside Gardens, Wheaton, MD

* photos taken on 4th of July in Washington, D.C.


* photo taken on October 17 2010 @ U.S. National Arboretum, D.C.

* photo taken on Aug 25 2011 @ Scott Arboretum, Swarthmore College, PA

* photo taken on Aug 17 2012 in Baltimore Co., MD

* photo taken on Feb 8 2014 @ U.S. National Arboretum, DC

* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photos taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

'Grandiflorus'
Much larger than average, deep yellow flowers up to 2 inches across.
Larger leaves, reaching up to 11.5 x 5 inches.

'Luteus'
Very fragrant pure yellow flowers.

'Mangetsu'
Double flowers.

Chimonanthus yunnanensis
A large shrub reaching up to 15 feet though has been recorded as large as 33 feet. It is very similar to Chimonanthus praecox and is native to southern China.
The rough textured oval leaves are medium green.
The fragrant, very pale yellow flowers are borne singly on stems over a year old.
Hardy zones 7 to 10.

Chimonanthus zhejiangensis ( Zhejiang Chimonanthus )
A vigorous, large, evergreen shrub, reaching up to 15 x 15 feet, that is native to forests in Zhejiang Province in southeastern China. Some records include: fastest growth rate - 6 feet. Endangered in the wild, it has much potential for horticulture as it is quite the stunning broadleaf evergreen.
The ovate to elliptical leaves are up to 5 x 1.6 inches in size. The foliage is glossy deep green above, bright green beneath.
The showy, fragrant, pale yellow to white flowers are borne from the leaf axils during mid to late autumn.
The smooth with lenticels bark is grayish-brown.
Hardy zones 7b to 9 in partial shade on well drained soil. It prefers regions with hot humid summers.

* photos taken on May 27 2017 @ Meadowlark Botanical Gardens, Vienna, VA