Clerodendron:  A Gem throughout Autumn

During my youth, November was my least favorite month.  School was in full furry, the days were getting shorter and the fall color was nearly finished.  Things just seemed gray and blah!  It is funny how 40 years can change ones perspective.  Granted, nothing has really changed, except now I really enjoy school!  It is where I work, and the slower pace of the upcoming winter brings promise that I will actually fulfill all those tasks that were beyond reach during the season.  However, the fact does still remain that the fall color has faded, and it is now part of my job to promulgate knowledge about plants that will provide interest at Rutgers Gardens when much is at rest.  One good suggestion is Clerodendron trichotomum commonly called Harlequin Glorybower.

Clerodendron is a member of the verbena family (Verbenaceae) and is a vast genus, covering tropical and temperate species in Asia and Africa.  Harlequin Glorybower is native to Eastern China and Japan.  For centuries the medicinal attributes of the leaves, stems and roots have been known for reducing hypertension and rheumatoid arthritis when ingested, while removing dermatological problems if applied topically.  By contrast, the fruit is poisonous and when pounded or ground into a powder it was used to kill lice!  The genus name is seemingly derived from its two applied uses.  Kleros is derived from the Greek meaning chance or chance of fate, perhaps referring to the beneficial properties of the vegetative materials and the poisonous aspects of the fruit.  Dendron means tree, so it is the Tree of Fate! 

In the garden, Glorybower typically grows to about 10’ high and wide and provides autumn interest that is difficult to match with other shrubs.  The flowers begin to appear in mid August and continue through October.  Individually, the 5 petaled, 1 ½” diameter flowers are not spectacular.  However, they are clustered into an inflorescence measuring up to 9” wide, providing a much greater show.  Not only are they visually attractive, the true appeal is the wonderful fragrance that drifts upwards of 15 feet from the plant.  It is particular noticeable in the evening and plants should be planted adjacent to patios and windows in order for the fragrance to be truly appreciated.  As the flower fades, the 5 leafy appendages that are below the flower (the calyx) thicken and turn red, providing a great backdrop for the developing metallic blue fruit.  Although the fruit is only the size of a large pea, its blue color is electric and it was used in Japan as a sky blue pigment for the coloring of fabrics.  The entire effect of the fruits with the numerous late blooming flowers makes it is easy to appreciate why this shrub is so spectacular in the August through November garden! 

Glorybower is reputed to be marginally hardy in central NJ and to spread rampantly by root suckers.  Interestingly, there has been a plant growing happily in Rutgers Gardens since 1997.  The plant is growing adjacent to Holly House and is now 12 feet tall and very happy!  This plant has also not spread, which is odd because I have seen the plant spread at rates up to 6’ in a season.  The foliage is large and somewhat pubescent, releasing a fragrance similar to peanut butter when broken.  Although the foliar odor is not terribly attractive, it does appear to have the redeeming quality of keeping deer at bay!  The fall color of the plant is a poor yellow at best and the winter interest is coarse.   The species epithet of trichotomum refers to branching into threes, which may refer to the branching pattern, which in winter displays a three pronged appearance.

November should never be a gloomy month, especially in the garden.  With fun plants like Harlequin Glorybower as part of the design pallet, fragrance and color can continue far longer than any young gardener could possibly imagine.

Last Modified: 11/02/2009, rugardens@njaes.rutgers.edu.
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