GREAT EVERGREEN GROUNDCOVER – Blechnum penna-marina
This small-scale hardy fern is very adaptable in the Pacific Northwest and makes a great year-round groundcover. Blechnum penna-marina, is happy in light shade but will grow in deeper shade as well as full sun if the soil is kept moist.
Blechnum penna-marina
The new foliage emerges bronzy-red, aging to deep green. The tightly packed fronds slowly spread by creeping rhizomes to form a very effective groundcover. Its variety B. ‘Cristatum’ is similar and its tips are curiously crested. In both forms the fertile fronds are reddish brown, thin and upright.
FAMILY NAME: Blechnaceae
COMMON NAME: Hardfern, alpine water fern
ORIGIN: New Zealand, South America
PREFERRED GROWING CONDITIONS: Moist, shady woodland spot in well-drained, acidic, humus-rich soil. Shade to part shade is perfect but will take full sun in the Pacific NW if kept moist.
MANAGEMENT: Groom in late winter or early spring. Remove old fronds as necessary. Cut well established plants to ground in late winter to fully appreciate the new foliage; recommended only on older clumps that have become ratty or are badly damaged by winter wet or snow cover.
PROPAGATION: Division in spring; sow spores in late summer
PESTS & DISEASES: None
COMPANIONS & USES: Heuchera, ajuga, dwarf polygonatum. Amongst rocks, in rockeries, niches, and walls.
IDEAL SPACING AT PLANTING TIME FOR FULL COVERAGE IN 2-3 YEARS: 8” on center or less. It can be a bit slow to spread in the beginning.
FOOT TRAFFIC: no
B. penna-marina, Little Hard Fern, is an evergreen fern with a Royal Horticulture Society Award of Merit. It’s height and spread in one year are 4” x 5” and in five years will reach 4-6” x 24”+. The foliage is dark green, small, leathery and glossy. Zone 5-8.
B. penna-marina ‘Cristatum’ is a bit smaller than the species.
Comments are closed.