Korean Rock Fern

Korean Rock Fern (Polystichum tsus-simense)

Korean Rock Fern is a compact, evergreen to semi-evergreen fern with glossy, finely cut fronds that form tidy clumps in shade. Its polished texture and neat habit brighten woodland edges, shaded borders, and containers.

Distinctive Features

Shiny, dark green fronds arch gracefully and hold structure in heat and humidity. Dense clumps provide year-round texture and contrast with broad-leaved shade plants.

Growing Conditions

• Sun Exposure: Partial to full shade; avoid hot afternoon sun.
• Soil: Moist, well drained, humus-rich soil; slightly acidic is ideal.
• Water: Keep evenly moist, especially the first seasons; tolerates brief dryness once established.
• USDA Hardiness Zones: 6 to 9.
• Mature Size: 1 to 1.5 ft tall and 1 to 2 ft wide.

Ideal Uses

• Focal Point: Glossy fronds add refined texture in shaded settings.
• Shade Borders: Finishes foundations and paths under trees.
• Rock Gardens: Thrives in crevices and well drained shaded niches.
• Containers: Reliable evergreen accent for shaded patios.
• Groundcover Masses: Close spacing forms a low, polished carpet.

Low Maintenance Care

• Watering: Water regularly to maintain even moisture; reduce frequency after establishment.
• Pruning: Remove tired fronds in late winter to make room for new growth.
• Fertilizing: Top-dress in spring with compost or a balanced, slow-release fertilizer.
• Mulching: Apply a 1 to 2 inch layer of leaf mold or fine bark to cool roots.
• Notes: Generally deer resistant and tolerant of humidity; ensure drainage to prevent crown rot.

Why Choose Korean Rock Fern?

• Year-Round Texture: Evergreen fronds keep shade plantings looking finished.
• Compact Habit: Fits small borders and understory pockets.
• Easy Partner: Pairs well with hostas, heucheras, and woodland perennials.
• Durable in Shade: Handles heat and brief dry periods better than many ferns.
• Low Input: Minimal grooming keeps clumps neat and healthy.

Site in protected shade with rich, well drained soil, mulch annually, and refresh fronds in late winter for a clean, vigorous display.