Crown Fern (Blechnum discolor): Distinctive New Zealand Fern

Overview

Crown fern (Blechnum discolor) is a striking, evergreen fern endemic to New Zealand. Its name refers to the distinctive "crown" of fertile fronds that stand erect in the center of the plant, contrasting with the arching, sterile fronds—a dramatic dimorphism characteristic of the genus Blechnum.

Botanical Description

Sterile fronds are pinnate, 50–100 cm long, arching gracefully, with dark green, leathery pinnae. Fertile fronds are narrower, more erect, 30–60 cm tall, with very narrow, brown, spore-bearing pinnae that stand like a crown above the sterile foliage. The rhizome is short-creeping, forming a dense clump. The specific epithet discolor means "two-colored," referring to the different appearance of fertile and sterile fronds.

Taxonomy

Family:	Blechnaceae
Genus:	Blechnum (BLEK-num)
Species:	discolor (DIS-kol-or)

Growing Conditions

• Light: Part shade to full shade.
• Soil: Moist, humus-rich, well-drained; acidic.
• Moisture: High; consistent moisture essential.
• Hardiness: USDA zones 8–10; frost-tender.

Garden Uses

Excellent for shaded, moist gardens in mild climates. The dimorphic fronds create a sculptural effect. Grow in woodland gardens, fern collections, or containers in sheltered courtyards. In colder zones, grow as a conservatory or houseplant.

Notes

One of the most recognizable New Zealand ferns. The Māori name is piupiu. In nature, forms extensive colonies on forest floors. Requires high humidity and protection from drying winds. Not drought-tolerant.