Polystichum tsus-simense: Korean Rock Fern
Korean Rock Fern
Synonym: Polystichum tsussimense
Position
- Partial to full shade
- Sheltered from strong winds
- North or east-facing aspects ideal
- Protected from direct afternoon sun
- Woodland settings perfect
- Urban gardens suitable
Hardiness
- Tolerates temperatures down to -20°C (-4°F)
- Evergreen in sheltered positions
- May need winter protection in exposed sites
- Performs well in urban areas
Soil Type
- Rich, moist but well-draining soil
- Humus-rich woodland soil type
- Adapts to acidic or neutral pH
- Cannot tolerate waterlogged conditions
- Benefits from organic matter incorporation
Soil PH
- Adapts to acidic or neutral pH
Height
- Height: 30-45cm (12-18 inches)
- Spread: 30-45cm (12-18 inches)
- Takes 3-5 years to reach full size
Seasons of Interest
- Evergreen finely divided fronds
- Fresh growth in spring with dark stems
- Mature fronds deep green
- Year-round architectural presence
- No flowers (ornamental fern)
- Black stems provide additional interest
Additional Notes
- Excellent for small gardens
- Perfect for container growing
- Low maintenance once established
- Suitable for urban conditions
- Regular mulching beneficial
- Avoid overhead watering
- Deer and rabbit resistant
- Good for urban gardens
- Works well under trees
- Benefits from annual removal of damaged fronds
- More compact than many ferns
- Does well in north-facing aspects
- Tolerates dry shade once established
- Good specimen plant
- Maintains shape without spreading aggressively
- Particularly attractive in winter
- Excellent contrast with other ferns
- Popular in Japanese-style gardens
- Creates year-round structure
- Good for small spaces and borders
- Dark stems add winter interest
Polystichum tsus-simense: Korean Rock Fern
The Korean Rock Fern brings refined texture and compact growth to shaded gardens. This Asian native combines durability with delicate appearance, making it perfect for various garden settings.
Physical Characteristics
Polystichum tsus-simense forms neat clumps reaching 30-45cm (12-18 inches) in height. The finely-cut fronds display dark green foliage with black stems. Each frond shows intricate detail and maintains good winter presence.
Growing Requirements
This adaptable fern thrives in partial to full shade conditions. It prefers rich, well-draining soil with consistent moisture. The compact root system suits both garden borders and containers.
Seasonal Interest
Spring brings fresh growth as dark stems emerge with new fronds. Summer sees the foliage develop deep green colours. Winter interest continues with evergreen fronds in sheltered spots.
Care and Maintenance
This low-maintenance fern needs minimal attention once established. Remove damaged fronds as needed throughout the year. Annual mulching helps maintain soil moisture and improves growing conditions.
Planting Tips
Plant in spring or autumn when soil conditions prove most favourable. Space plants 30cm (12 inches) apart to allow for mature spread. Ensure good soil preparation with added organic matter.
Soil Requirements
Polystichum tsus-simense adapts to most soil types but prefers rich, well-draining conditions. It grows well in both acidic and neutral soils. Adding leaf mould or garden compost improves growing conditions.
Companion Plants
This fern pairs beautifully with other shade-lovers. Consider combining with hostas, heucheras, and spring bulbs. The dark stems provide excellent contrast throughout the growing season.
Container Growing
The Korean Rock Fern grows successfully in containers. Use pots at least 30cm (12 inches) deep with reliable drainage. Regular watering proves essential for container specimens.
Problem Solving
This robust fern rarely encounters serious problems. Occasional brown fronds might appear during extended dry spells. Remove damaged growth promptly to maintain appearance.
Climate Tolerance
The Korean Rock Fern shows excellent hardiness, withstanding temperatures down to -20°C (-4°F). It performs well throughout the UK, particularly in sheltered locations.
Final Thoughts
Polystichum tsus-simense offers gardeners a versatile and reliable choice for shaded areas. Its refined appearance, compact nature, and year-round presence make it valuable in various garden settings. This low-maintenance fern brings sophisticated texture and dependable performance to challenging shade conditions.
The combination of dark stems, finely-cut fronds, and evergreen nature creates lasting appeal. Whether growing in borders, woodland gardens, or containers, the Korean Rock Fern proves itself as an essential addition to any shade garden design.
The fern’s ability to thrive in various conditions, combined with its attractive appearance, makes it perfect for both small and large gardens. Its presence adds sophistication and structure to areas where many plants struggle to establish.
Check out the RHS article here.
For more information on ferns for your garden please click here.
Frequently Asked Questions
Q: How tall does Polystichum tsus-simense grow?
A: Polystichum tsus-simense typically reaches heights of 30-45cm (12-18 inches). Its compact growth makes it perfect for small spaces and shaded areas.
Q: What are the ideal growing conditions for this fern?
A: This fern thrives in partial to full shade. It prefers rich, well-draining soil that retains moisture without becoming waterlogged.
Q: How hardy is the Korean Rock Fern?
A: The Korean Rock Fern can tolerate temperatures down to -20°C (-4°F). It adapts well to various conditions in the UK garden.
Q: What type of soil does it prefer?
A: Polystichum tsus-simense flourishes in rich, well-draining soil. It grows well in both acidic and neutral pH conditions.
Q: Does it require a lot of maintenance?
A: Once established, the Korean Rock Fern requires minimal maintenance. Remove any damaged fronds as needed to keep it looking healthy.
Q: Can I grow it in containers?
A: Yes, this fern can thrive in containers. Use pots at least 30cm (12 inches) deep with good drainage to support healthy growth.
Q: What plants pair well with Polystichum tsus-simense?
A: This fern pairs beautifully with other shade-lovers like hostas and heucheras. Its dark stems and fine fronds provide great contrast in plantings.
Q: How often should I water it?
A: Water regularly during dry spells, especially for young plants. Established ferns need watering mainly during prolonged dry periods.
Q: What should I do if the fronds turn brown?
A: Brown fronds often indicate drought or damage. Trim away any affected fronds, and ensure the plant has adequate moisture.
Q: Is it suitable for full sun?
A: Polystichum tsus-simense prefers shade. While it can tolerate some sun, full sun exposure may lead to frond stress and browning.