Athyrium niponicum, the Japanese painted fern, is a species of fern native to East Asia, primarily Japan, North China, Korea and Taiwan. Athyrium niponicum occurs in temperate regions in shady places in the lowlands.
Athyrium niponicum is a deciduous herbaceous plant with a weeping habit, being one of the most colourful garden ferns. It is a terrestrial fern with creeping rhizomes and with a whorl of fronds growing from the basal rootstock. The fronds are triangular shaped blades, 25-40cm (10-16 inch) tall and 15-25cm (6-10 inch) broad, pinnate, with 6-10 pairs of pinnae 4-9cm (1.5-3.5 inch) long and 2-3cm (0.8-1.2 inch) broad, deeply lobed. The fronds are bright green with a dark red-brown stem in the wild plant. This fern has a low and mounding habit, slowly spreading by rhizomes to form dense colonies. The fronds are positioned in a way that creates a horizontal layering effect. Its colorful foliage should be vibrant from early spring until frost, when it will go dormant and reemerge with its excellent foliage the next spring. Mature fronds hold color and contrast with emerging fronds to form a compact clump.