Dryopteris erythrosora

Botanical identity and natural origin of Dryopteris erythrosora

Dryopteris erythrosora is native to temperate East Asia, including China, Japan, Korea, Taiwan and the Nansei-shoto islands. It is widely known as the autumn fern or copper shield fern, names inspired by the warm colours of its fresh fronds.

Care for Dryopteris erythrosora as a container fern

• Light: Give medium to bright filtered light. Gentle direct sun is suitable, especially early or late in the day.
• Water: Keep the soil consistently moist while new fronds are forming. Water when the surface starts to dry and let excess water drain.
• Temperature: Cool to moderate room temperatures are best. A cooler position with gentle airflow suits the fern well.
• Humidity: Average room humidity is usually enough when soil moisture stays steady. In heated rooms, raise humidity around the plant.
• Substrate: Use a rich, airy mix that holds moisture and drains freely.
• Feeding: Apply a dilute balanced fertiliser every 4–6 weeks while new fronds are opening. Pause feeding when growth slows.
• Grooming: Cut fully brown or damaged fronds close to the crown with clean scissors.
• Repotting and propagation: Repot when roots fill the pot or the mix becomes compacted. Established clumps can be divided during repotting, keeping roots and a growing crown on each section.

Frond and crown health of Dryopteris erythrosora

• Frond tips turn crisp and brown: The soil has dried too far or hot, dry air is reaching the foliage. Water evenly and move the fern away from heaters or harsh direct sun.
• Pale tan patches appear on exposed fronds: Strong direct light has scorched the leaf tissue. Move the plant into filtered light and leave healthy green tissue in place.
• Several fronds yellow and the crown becomes soft or dark: Prolonged wetness has caused rot. Cut rotten tissue back to firm healthy tissue with a clean tool and discard it, then repot the healthy crown in fresh airy mix.

Keep Dryopteris erythrosora away from children and pets

• Keep this plant away from children, cats and dogs.
• Its effects after chewing or swallowing are unclear, and plant material can still cause an upset stomach.
• Contact a veterinarian or medical professional if symptoms develop or do not settle.

How did Dryopteris erythrosora get its name?

Dryopteris combines Greek drys, meaning oak, with pteris, meaning fern. The epithet erythrosora combines Greek erythros, red, with soros, a spore heap, and refers to the red sori or their coverings.

Michel Adanson established the genus Dryopteris in 1763 in Familles des plantes, volume 2, pages 20 and 551.

Daniel Cady Eaton first described it as Aspidium erythrosorum in 1857 in Narrative of the Expedition of an American Squadron to the China Seas and Japan, volume 2, page 330. Carl Ernst Otto Kuntze later placed it in Dryopteris as Dryopteris erythrosora in 1891 in Revisio Generum Plantarum, volume 2, page 812.