Cinnamon Fern: A Unique Native Fern with Dramatic Fertile Fronds

Ferns bring instant tranquility to shade gardens. Cinnamon fern (Osmunda cinnamomea) is one of eastern North America's most distinctive natives, found in foggy Appalachian mountaintop habitats. Its namesake cinnamon-colored fertile fronds emerge in early spring, followed by graceful fiddleheads that unfurl into lacy green sterile fronds.

Quick Facts

• Botanical name: Osmunda cinnamomea
• Common name: Cinnamon fern
• Origin: Eastern North and South America, eastern Asia
• Hardiness: USDA zones 3–9 (–40 °F)
• Light: Partial to full shade
• Water: Medium to wet soil
• Mature size: 2–4 feet tall and wide; wet soil maximizes size
• Benefits: Deer, rabbit, slug resistant; no serious diseases; tolerates heavy shade and wet soil; fails in dry, sunny sites
• Seasonal interest: Erect cinnamon fertile fronds early spring; fiddleheads unfurl to green fronds; yellow autumn color; winter dormancy
• When to plant: Spring best

Distinguishing Traits

The fertile fronds are cinnamon-colored and powdery in texture. Cinnamon fibers at the plant base have been used historically as orchid potting medium. The frond dimorphism—separate fertile and sterile fronds—is unique among garden ferns.

Design Uses

• Plant in groups for strongest statement—mimics natural habit
• Poorly drained areas, pond edges, near outdoor faucets
• Avoid dry or sunny sites

Planting Notes

• Site in moist, shaded areas.
• Amend soil with compost; mulch with shredded hardwood or leaves.
• Water 2–3 times weekly until established.

Photo by Nicholas A. Tonelli