Athyriums are cold hardy, Northern Hemisphere ferns with a few freeze-tolerant strays from temperate South American locales. With limited options from Europe or North America, many of our truly ornamental garden athyriums were introduced from the fern-rich forests of Japan, China, and Korea. Others have been introduced from the outlying areas of the Himalayas. These imports offer a delightful array of subtle to remarkable foliar color and forms to enrich the woodland
Astrolepis sinuata shares the landscape with cactus in the University of California Botanical Garden at Berkeley.
The Japanese painted fern, Athyrium niponicum 'Pictum', growing in tandem with a Japanese maple, Acer palmatum 'Ukigumo'.
palette. Among the many choices, the popular and incredibly adaptable Japanese painted fern is one of the most universally recognized and functional of all gardenworthy ferns.
Athyriums have had a complicated nomenclatural history. Until 1800 they were included in the genus Asplenium, presumably due to the similarity of the indusia. Meanwhile, Deparia and Diplazium, having once been members of the house of Athyrium, with many common characteristics, have been splintered off as separate genera. Relatively shallow stipe grooves, which do not extend to the rachis, separate Deparia, and bivalved indusia distinguish Diplazium. Not surprisingly many of the segregate species are still classified as athyriums in literature, Web sites, and nursery catalogs.
There is no official derivation for the name Athyrium. Some authors suggest the Greek a, without, and thyrium, shield or door, in reference to the late opening or lifting of the indusia; others advocate "sporty" or "to sport." However, in light of the multitude of lady fern cultivars, my favorite, also from the Greek, is athoros, "good at breeding."
Worldwide there are approximately 200 species, more than 60 hybrids (mostly from Japan), and, at one time, within Athyrium filix-femina alone, almost 300 cultivars. I would also like to emphasize (emphatically) here that filix is not spelled felix and the niponicum of the Japanese painted fern has only one p please.
Almost all athyriums are deciduous. The North American natives adjust, usually with exceptional ease, to sites with varying degrees of shade cover to moist, sun-drenched locales. Stout, sometimes branching, rhizomes are erect to long-creeping. Grooved stipes of definitive, assorted colors are usually swollen at the base where whatever scales that may be present are concentrated as well. Blades, with free veins, range from short to tall and modestly pinnate to sumptuously quadripin-nate. Back-to-back C-shaped vascular bundles merge into a U in the upper regions of the stipes. Sori and indusia are variously shaped as an upside-down hooked J, horseshoe, crescent moon or, rarely, rather linear.
The fronds lack the strengthening tissue of other fern genera and consequently are structurally delicate and easily snapped. The planting site should be chosen accordingly— away from cruising dogs, feisty squirrels, prevailing winds, and wayward watering systems (including people with a hose in hand). Some species produce fronds continuously throughout the season, and some, particularly the west coast lady fern, even while still producing new fronds can look tattered by midsummer. All appreciate moist, acid soil, withthe western lady, Athyrium filix-femina subsp. cyclosorum, forming 6-ft. (1.8-m) shaggy spires of dense foliage in wet marshlands, towering well above the 3- to 4-ft. (90- to 120-cm) height of the mature male fern.
Fall color comes to Athyrium alpestre in the Cascade Mountains of Washington State.
Not surprisingly, since these ferns are universally common, they have a rich historical collection of associated herbal remedies. Powdered extracts from the rhizome of Athyrium filix-femina, like similar concoctions from Dryopteris filix-mas, were a multipurpose cure for an abundance of ills especially for purging the systems of humans and animals of worms. More romantically, or at least less graphically, adding sprigs of Athyrium foliage to the casks of curing wine was reputed to keep the wine from spoiling.
Propagation is problem-free. Spores germinate readily (sometimes far too freely) in culture or in the garden, and division, especially for those with branching rhizomes such as Athyrium niponicum 'Pictum', is strictly a matter of timing and a sharp knife. While the species generally breed uniformly from spores, most of the cultivars need to be propagated by division or tissue culture to remain true to name and retain their unique characteristics.
With their exceptional hardiness and range of shapes and colors, there should be an Athyrium suitable for, and decorative in, most any landscape design.
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