Diphylleia cymosa
Umbrella leaf (Diphylleia cymosa) has enormous umbrella-like leaves in spring and tiny white flowers that follow. But the show stopper season is summer. That’s when dramatic blue berries high up on red stalks rise above the plant. The plant is telling you to look. And everybody does.
Native to eastern North America, this herbaceous perennial is a shade lover and flourishes in moist rich soil. It grows to a height and spread of 1 m/3 ft. Umbrella leaf is closely allied to mayapple (Podophyllum peltatum). Some sources have put umbrella leaf into the same genus.
But there are two other species of umbrella leaf to think about. One in Japan, D. grayi and the other in China, D. sinensis. All three share similarities despite the geographical distance. When this happens, it’s called plant disjunction. There are quite a few plants from eastern North America similar to ones in eastern Asia. And this is how it could have come about:
Major climatic changes occurred toward the end of the Tertiary (65-2 million years ago) and the world entered a glacial period. Polar ice caps expanded and the temperate forests died. In parts of China and eastern North America conditions remained warm enough for relict flowering plants to survive. The mountain ranges there run north-south. Plants retreating before the glacial advance were able to reach warmer latitudes. Europe and much of Asia have transverse mountain ranges, such as the Alps and Himalaya. Their icecaps prevented southern migration.
These summer pictures of umbrella leaf were taken in bed 16 - near a path through the Eastern North America Garden. Perfectly placed. Not one person missed their show.
Text and photos by Hughie Jones