I first came to know umbrella leaf (Diphylleia cymosa) through a case of mistaken identity. While visiting a Seattle garden in the late 1980s, I was astonished by an herbaceous perennial growing in a shaded border, with pairs of beefy, shiny, peltate (umbrella-like) leaves atop split petioles. Like any keen gardener, I asked excitedly about its identity and immediately forgot what I was told. I did remember, however, that the plant had come from We-Du Nursery in North Carolina.
Upon receiving the We-Du catalog, I came upon the listing for Diphylleia cymosa, which was described as a bold-leaved perennial with two large rounded leaves per stem, and clusters of white flowers atop two-foot stems in early spring that later result in handsome blue fruits. It was obvious that this was the plant I had seen, and I immediately ordered three. When they arrived, I was crestfallen to discover that it wasn’t the species I sought (which, I later discovered, was actually Podophyllum pleianthum).
Though I grudgingly planted my trio of undesired plants in my woodland garden, I completely ignored them for the first two years as they settled into place. The third spring, however, my ugly ducklings emerged with a swanlike vitality and presence, and my interest in the genus Diphylleia was sealed. Diphylleia cymosa, like the podophyllum that I so admired, is an herbaceous representative of the barberry family (Berberidaceae); in fact, the two genera are quite closely related. The genus name Diphylleia (literally, “two leaves”) aptly describes this plant, which offers a pair of immense, jagged-edged, rounded leaves on each stem, ultimately forming mounds of several stems to three by three feet. The cymes (hence the specific epithet cymosa) of white flowers are produced on narrow stems that rise well above the foliage in mid-June. As the crops of large, stunning, succulent blue fruits ripen in late summer, the pedicels change in color from green to an intense coral red.
In the summer of 2003, I had the opportunity at last to see D. cymosa in its native habitat along streams in moist, shaded sites relatively high in the Blue Ridge Mountains of western North Carolina (its natural range extends from Virginia south to Georgia). Despite its relative abundance in the wild, as well as its hardiness and adaptability, it has never been as widely planted as it deserves.
Worldwide, there exist only three species of Diphylleia. Along mountain streams in northern Japan can be found D. grayi, which is superficially similar to our American native. I’ve collected seed and raised the progeny in my garden, but it doesn’t offer the impressive foliage or fruit display of its American cousin. The third species, D. sinensis, occurs in western China, where I have encountered it on Mt. Emei, in Sichuan Province, again at higher elevations. The bold, jagged leaves of this species emerge in a seductive coppery tone that later fades to green. The plants in my garden haven’t flowered or fruited yet, so I can’t compare them to their brethren.
Propagation of diphylleias is primarily through seed, which germinates readily after a single cold treatment. The seedlings won’t blossom for at least three years after being planted out in the garden. Despite their natural affinity for very wet soils, I have successfully grown D. cymosa in sharply drained soils that receive regular supplemental irrigation during the growing season. Its gallant foliage brings to any woodland vignette the excitement of bold texture, which is so often needed for a satisfying composition. Success with D. cymosa has been reported across the northern tier of states as well as on the marine slopes of the Pacific Northwest. I would be interested in hearing from other gardeners who have successfully cultivated this species in the humid lowlands of the Southeast or in drier climates (e-mails may be sent to firstname.lastname@example.org).
As with many other things in gardening and life, making mistakes can lead to vastly pleasurable experiences that would have otherwise been missed. I will always be thankful for my error in ordering D. cymosa.
TYPE OF PLANT: herbaceous perennial
FAMILY: Berberidaceae (barberry family)
ORIGIN: in moist soils in the Blue Ridge Mountains from Virginia to Georgia
HEIGHT/SPREAD: 1–3 ft./1–3 ft.
LEAVES: peltate, rounded, toothed, deeply cleft, mid-green, to 16 in. across
FLOWERS: small, white, 6-petaled, borne in a flat cyme
BLOOM PERIOD: brief, in late spring-early summer
FRUITS: a globose berry ripening to blue, 1/2 in. in diameter, very striking
HARDINESS: USDA Zones 4–9
EXPOSURE: partial sun to shade
SOIL: retentive, rich in organic matter
MOISTURE NEEDS: high
PROPAGATION: by fresh, cold-stratified seed
PROBLEMS: none serious