Polystichum munitum (Western Sword Fern, Sword Fern, Giant Holly Fern)


Botanical Information

FamilyDryopteridaceae
GenusPolystichum
Speciesmunitum
CategoryPerennials
TypeFerns
OriginGenus name originates from the Greek word 'polys' meaning many and 'stix', which means a row, in reference to the rows of spore clusters called sori on the underside of fronds. Native to North America.

Details

USDA Hardiness Zone1a - 6a
USDA Hardiness Ref.
Canadian Hardiness Zone0a - 5b
Canada Hardiness Ref.
RHS Hardiness ZoneH7
RHS Hardiness Ref.
Temperature (°C)-51 - (-21)
Temperature (°F)-60 - (-5)
GrowthMedium

Description and Growing Information

General DescriptionPolystichum munitum is a hardy evergreen fern with short rhizomes and linear, leathery fronds.
LandscapeFerns make a nice addition to herbaceous borders, rock and cottage gardens or as an underplanting of roses and shrubs.
PropagationBy spores or division in the spring.
CultivationGrow in part sun to full shade, in moist, well-drained soil with a pH of 6.5 - 7.5. In shade and water-retentive soil it will tolerate dry conditions. Good drainage is essential.
PestsPolystichum are susceptible to a fungal disease called Taphrina wettsteiniana, identified by black lesions on the upper surface of fronds and layer of white spores underneath. In spring, it is wise to remove old fronds that could be infected. Peach leaf curl is another possible problem.
Bark/Stem DescriptionYoung plants are covered in dense brown scales.
Leaf DescriptionGreen, acuminate with margins serrate to biserrate, arranged pinnately (in rows directly opposite) up to 40 per side on stipes (stalks) up to 18 cm long with dense scales near the base. The whole frond can grow up to 19 cm long, evergreen, with a leathery texture.

Photographs