Blechnum Fern

Blechnum (hard fern) is a genus of between 150–220 species of ferns with a cosmopolitan distribution, in the familyBlechnaceae in the eupolypods II clade of the orderPolypodiales. By far the greatest species diversity is in tropicalregions of the Southern Hemisphere, with only a few species reaching cool temperate latitudes in the Southern Hemisphere (notably B. penna-marina, south to Cape Horn, Chile, thesouthernmost fern in the world) and Northern Hemisphere(notably B. spicant, north to Iceland and northern Norway).

Most are herbaceous plants, but a few species (e.g. B. buchtieniiand B. schomburgkii in Ecuador) are tree ferns with stems up to 3 m tall. Blechnum varies from most ferns in having a separation of sterile (photosynthetic) and fertile (reproductive) fronds in the same plant.

The sterile leaves have flat, wavy-margined leaflets 5 to 8 millimeters wide, while the fertile leaves have much narrower leaflets, each with two thick rows of sori on the underside.

B. spicant is hardy and evergreen, growing to 0.5 m (1 ft 8 in). It has gained the Royal Horticultural Society's Award of Garden Merit