
CHILEAN HARD FERN Blechnum chilense cordatum parablechnum
Parablechnum cordatum (synonyms Blechnum cordatum, Blechnum chilense), the Chilean hard fern or costilla de vaca, is a fern which grows to 0.9–1.8 m (2 ft 11 in–5 ft 11 in), often developing a trunk-like appearance over time. This plant has gained the Royal Horticultural Society's Award of Garden Merit. The 'seeds' are actually spores, and are extremely tiny.
Type: Hardy perennial
Height: 5-6 feet
Hardiness zones: 7-9
Seeds per pack: 10 spores
Germination: It is important to use a sterile seed-start mix, or sterile a mix with boiling water, before planting. Use a pot with holes so water can drain. When cool, sow spores on the surface of the mix. Watering should be done from the base only (from a bottom tray), as watering from the surface will bury the seeds and they cannot grow. Cover the pot with clear plastic, and keep in a well lit location as light is required for germination. Do not place in direct sun. The ferns can take weeks or months to germinate.