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Gardening in the Rainy Zone.
KOREAN ROCK FERN, TSU-SIMA HOLLY FERN
Sunset zones: 4-7, 14-24.
USDA zones: 6-9.
Heat zones: 9-5.
Height: 8-20 inches (20-50 cm).
Width: 16 inches (40 cm).
Bipinnate, dark green, semi-evergreen fronds with black veins.
Part to full shade.
Rich, fertile, well-drained soil.
Sow spores in summer.
Divide in spring.
Trim off dead fronds.
Pests and Diseases:
Problems with these plants are very rare.
Rainy Side Notes
Easy to grow, this dainty fern, P. tsus-simense, is one of my favorites of the polystichums. Inserted into shady areas of rock walls or planted in any well-drained soil, its small size means you can tuck it in almost anywhere in the garden.
In our maritime climate in the Pacific Northwest, the fern can take some sun. It takes to container culture, which means it's an excellent candidate for indoor growing, and a choice fern for a pot in a shady area of porch or deck. Furthermore, the fronds stay semi-evergreen to evergreen most of the time, making it useful for a year-round presence wherever it's growing, provided you keep the soil moist at all times. The dark stems contrast beautifully with its green fronds.
Photographed in author's garden.