Blechnums are a colorful collection of mostly tropical and subtropical species that rejoice in humid-rich environments and excel in moist to spongy acid soil. They are shade-loving
understory plants of forest floors, road banks, and mountainsides, often carpeting their native habitats with blankets of showy, rosy red, luminous foliage. With many species offering their new growth in these pleasing tints from pink to rose to bronze, they are welcome accents in both garden and home environments.
The name Blechnum is derived from the Greek blechnon, an ancient name for fern. The world's 180 to 200 species are concentrated in the Southern Hemisphere with New Zealand, Chilean, and Australian natives offering a potpourri of hardy and potentially hardy species of horticultural interest. Structurally they are a fairly uniform group with evergreen, pin-
natifid to once-pinnate blades. Rhizomes are usually erect or occasionally creeping, and in some species may form a modest trunk.
In the 1800s blechnums were distinguished botanically from lomarias (loma, an edge, referring to the position of the sori on the fronds). The latter, hardly a familiar classification today, referenced dimorphic species, that is, with dissimilar sterile and fertile fronds. Fertile pinnae in the dimorphic types consisted, then as now, of contracted slits of foliage and deciduous elongate linear sori totally covered with an indusial membrane. Pure blechnums were monomorphic with their sori located medially on fertile pinnae. Blechnum classification
Brilliant new growth on Blechnum chilense in the Alerce Andino National Park in Chile. Photo by Richie Steffen, Miller Botanical Garden.
Rosy new growth on Blechnum appendiculatum.
today includes both the dimorphic, producing fronds that are exclusively sterile or fertile, and the less common monomor-phic types. Veins are free and the vascular bundles of various sizes are arranged in a circular manner looking (given some imagination) similar to an asymmetrical smiley face.
Propagation from spores is an inconsistent science. All species should be sown as soon as practicable after the spores mature. In general I find that monomorphic types tend to germinate more promptly and with greater vigor. Dimorphic species vary. Some such as Blechnum discolor have remarkably short-lived spores and unless sown immediately upon ripening deliver a minimal to nonexistent percentage of progeny. To add to the difficulty, there are intermediates that germinate (generating enthusiasm) and then fade when the budding sporelings are given their first transplant. Blechnum niponicum and even B. spicantcome to mind. Division is an excellent option but, until more Southern Hemisphere species are in general cultivation, limited by the lack of ready material and the minimal numbers that produce creeping rhizomes. Known hybrids are few although they do mix it up a bit where habitats overlap in Mexico and occasionally in New Zealand.
Unlike many ferns, blechnums do not have an illustrious history of miraculous offerings of herbal cures. Britten (1881), in his delightfully informative and intellectually entertaining book, European Ferns, comments rather apologetically on the "hard fern" (the vernacular name for B. spicant, aka Lomaria spicant in those days): "in the good old times, when no plant was considered entirely destitute of'virtues', it was not regarded as quite useless." He goes on to recommend a concoction of dried fronds and vinegar to dissolve hardness of the spleen.
Though only a few qualify as hardy, those blechnums that do are an elite addition to the moisture-nourished woodland garden. All offer a tidy year-round presence, and many are especially glamorous when unfurling their fronds in rainbow shades of red, pink, and rose before quieting to variations of green. I recommend them strongly for their refreshing indoor and outdoor visual enrichment.
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