Osmundastrum cinnamomeum

This fern forms large, upright, vase-shaped clumps. Its sterile (foliage) fronds can reach a height of 0.6 - 1.5 m (2-5 ft) and spread about 0.6 - 1 m (2-3.3 ft) wide. It expands slowly by rhizomes, forming increasingly wider clumps over time.

Deciduous. The sterile fronds are a beautiful light green, turning medium green as they mature, and are deeply pinnatifid (lobed). In autumn, they often turn attractive shades of yellow or cinnamon brown. The distinctive fertile fronds emerge in spring as separate, erect, non-leafy stalks covered in cinnamon-colored sporangia (spore cases), giving the fern its common name. These fertile fronds wither after spores are shed, usually by mid-summer.

This is a fern, so it does not produce flowers. It reproduces via spores, which are borne on the specialized fertile fronds in spring.

Thrives in partial to full shade. While it can tolerate some morning sun in cool climates, it prefers consistently moist, shaded conditions. It's best to protect it from harsh afternoon sun, which can scorch its fronds.

Excellent frost hardiness (USDA Zones 2-10). It is very cold tolerant and reliably overwinters outdoors in temperate regions.

Prefers rich, moist to wet, humus-laden, acidic soil. It naturally grows in swamps, bogs, and alongside streams. Good drainage is important to prevent waterlogging, but the soil should never dry out. It tolerates constantly wet conditions better than many other ferns.

Ideal for woodland gardens, bog gardens, rain gardens, pond or stream margins, shaded borders, and naturalized areas. Its bold texture and upright form make it a striking specimen or mass planting. It's generally deer and rabbit resistant.

High water requirement. Needs consistently moist to wet soil. Do not allow the soil to dry out, especially during hot periods.

Relatively low maintenance. Provide a good layer of leaf mold or compost annually to maintain soil moisture and fertility. No pruning is generally required, but old, tattered fronds can be removed in late winter or early spring before new growth appears.

Containerized plants can be planted from spring to early autumn.