This June, Michelle and I were invited to see the “stumpery” of Pat and Walt Riehl on Vashon Island in the Puget Sound. We crossed the sound on one of Washington State’s many ferries, accompanied by our long-time horticulture friend Stephen Lamphear. Pat’s stumpery, started in 2006, was the first stumpery constructed in the Pacific Northwest. The Riehls were inspired to create this work of horticultural art after seeing ferneries and stumperies on a trip to England guided by Martin Rickard, noted fern expert and past president of the British Pteridological Society. Rickard later “crossed the pond” to help the Riehls design their garden on Vashon. One of the key focal points in this exquisite garden are the numerous tree ferns, Dicksonia antarctica, scattered throughout the stumpery. Native to Eastern Australia and Tasmania, this beautiful tree fern can grow to 30 feet in the wild. In cultivation it is generally much smaller. The species typically reproduces from spores, and after several years of growth, a dark trunk begins to form. The trunk continues to grow taller as lower fronds die and break off. It is commonly called Tasmanian tree fern, or soft tree fern, and specimens can be grown in USDA Zone 8 with protection and easily in Zones 9 and 10. It will tolerate light frost. In colder climates, D. antarctica can be grown in containers and moved into a greenhouse or conservatory for the winter. It thrives in areas with hot, humid summers. Just because it’s not hardy in the ground in a given area is no reason not to grow this great plant.
Dicksonia was named after James Dickson (1738-1822), noted British botanist and nurseryman. There are about 25 species in the genus. All but one, Dicksonia sellowiana, are native to the Southern Hemisphere. D. sellowiana is native from Southern Mexico through Central America and Northern South America.