The allure of Kirengeshoma Palmata

I’ve designed, maintained and enjoyed shade gardens for over 30 years and always get excited when including plants with significant “presence.” Being a fan of big and bold foliage, I’m never shy about including plants like Ligularia , Rodgersia , Hosta and ‘Sun King’ aralia (Aralia cordata ), a personal favorite. When I stumbled upon yellow wax bells (Kirengeshoma palmata ) at the Chicago Botanic Garden over 15 years ago, I knew I had found another amazing shade perennial and continue to be impressed by this member of the Hydrangeaceae family.

Native to mountainous areas of Japan, Korea and China, this clump-forming perennial (USDA Zones 4-8) reaches shrub-sized proportions, at maturity, of four feet in both height and width. I’ve seen specimens in the Pacific Northwest well over 6 feet tall. Strong, upright, sturdy stems support large, palmate, deeply-lobed and toothed, oppositely-arranged leaves reminiscent of maple or sycamore. The foliage, up to 8 inches across, is dramatic and quite unique. This graceful addition to the shadier border is quite bold as a textural element and backdrop for neighboring plants. Yellow wax bells prefers moist, well-drained locations with humus-rich soil to thrive. Supplemental watering during dry periods is essential as well. Kirengeshoma is both deer and rabbit resistant with very few insect or disease problems.

I would plant this perennial simply for the foliage but the added benefit of late summer, buttery-yellow flowers add even more appeal to this robust selection. The rounded buds in summer open in drooping flower clusters featuring 3-5 flowers, each with five petals. The flowers present as a broad, “bell-shape” with petal tips turned outwards. I describe the flowers as appearing like they still want to open more! Regardless, they are certainly showy and long-lasting as are the seed capsules. Fall color can be a nice gold but a hard frost will finish the season for yellow wax bells. There are some newer, varietal selections of this perennial that are intriguing (chartreuse foliage and variegation). Closely related Kirengeshoma koreana has very similar characteristics although blooms a bit earlier with more upright and outward facing flowers and features smaller leaves. Sourcing these plants has been challenging.

Mark Dwyer is currently the garden manager for the Edgerton (WI) Hospital Healing Garden after 21 years as director of horticulture at Rotary Botanical Gardens (Janesville, WI). He also operates Landscape Prescriptions by MD, a landscape design and consultation business. mcdwyer@zoho.com