Flowers and fruit may be present at the same time on harlequin glorybower. Photo by Robert Mayer.
While some Arboretum plants are looking a bit worn out now in late summer, the fabulously named harlequin glorybower [pdf] (Clerodendrum trichotomum) is just coming into its own. Though its habit–a large, irregular, vigorously suckering shrub–leaves something to be desired, it more than makes up for that with late season bloom followed by showy autumn fruit.
Harlequin glorybower has a wide native range that includes Japan, China, and Korea. Cold hardiness is often listed as USDA Zone 7 or 8 but there is certainly variability depending on provenance. Many specimens at the Arboretum (Zone 6) have survived as dieback shrubs (stems dying to the ground over winter) but others have had more persistent stems. The collections include wild-collected accessions from Korea (1702-77*MASS) and China (1921-80*MASS).
A tiger swallowtail butterfly sips nectar from harlequin glorybower flowers (842-79*MASS). Photo by Nancy Rose.
The large leaves of harlequin glorybower are dark green, ovate, and smell curiously like peanut butter when crushed. But right now it’s the flowers that will grab the attention of your eyes and
nose. Starting typically in late July, harlequin glorybower bears large, loose clusters of marvelously fragrant white flowers subtended by balloon-like pink calyces. The flowers, which are produced over a month or more, are a magnet for hummingbirds, butterflies, honeybees, and other pollinators. The flowers are followed by fruits–single, beadlike, almost metallic bright blue drupes, strikingly set within the now open, star-shaped rosy pink calyces. Seek out specimens at the Arboretum now for some late summer aromatherapy (the sweet-spicy scent reminds me of summersweet, Clethra alnifolia
, a native shrub that’s also blooming now).
Nancy Rose, editor of Arnoldia