Classification, origin and description
Common name: Fern.
Etymology: derives from the Greek "nephros", kidney and "lepis", scale, due to the shape of the membrane that serves as a shelter for spores (the indusio).
provenance: tropical areas.
Genre description: includes about 30 species of evergreen or semi-evergreen, epiphyte or terrestrial ferns, which, from the stoloniferous rhizomes, emit tufts of pinnate or bipennate fronds, formed by articulated pinnules in various forms, which on the whole appear slender, arched, sometimes hanging. They are plants suitable for growing in a greenhouse or apartment, in hanging pots or baskets.
Nephrolepsis (website photo)
Species and varieties
Nephrolepsis acuminata: originating from Malaysia and the Sonda islands, this fern has erect fronds, which can reach the length of one meter, formed by large pinnules with different appearance depending on the variety: composed in the "Multiceps" variety; rippled in the variety "Furcans plumosa".
Nephrolepsis cordifolia o N. tuberosa: native to New Zealand, Japan and Oceania, this evergreen fern has fronds, even 60 cm long, arched at the end formed by small bright green pinnules. It grows up to a meter in height. on the market there are several varieties, among which we remember: "Compacta", of reduced size; "Crispato-congesta", with ruffled pinnules; "Duffii", with thin fronds and small pinnules; "Plumosa", with hanging branches, up to 150 cm long, formed by sickle-shaped pinnules.
Nephrolepsis exaltata: the fronds of this species, which represents one of the most cultivated ferns, can reach 180 cm. long and are pinnate, rigid and curved, formed by thin, notched and slightly rippled pinnules of bright green color. The type species with almost completely erect branches is hardly cultivated. On the market, on the other hand, there is a vast assortment of varieties and cultivars that can significantly differentiate in terms of bearing, length and appearance of the fronds, which can become bipinned, tripennate, more or less septate, curled and with a feathery appearance. Among the best known are: "Bostoniensis", with larger and faster growing branches than the type species; "Childsi", with small fronds only 30 cm long; "Elegantissima", with multi-plotted fronds made up of double pinnules; "Hillii", characterized by fronds of light green color, rippled and bipinned; "Magnifica", with lace-like fronds, 30-40 cm long .; "Marshallii", with large light green, crenate fronds; "Roosveltii", with pinnate fronds and wavy pinnules; "Roosveltii plumosa", with very jagged and wavy pinnules; "Whitmanii", with 45 cm long fronds. more rippled than normal.
Nephrolepsis tesselata: this fern has fronds, up to 90 cm long, hanging, dark green in color, with thin and blackish stems.
Environmental requirements, substrate, fertilizations and special precautions
Temperature: the minimum winter temperature must not be lower than 10 ° C. In the winter period ferns suffer greatly from the low environmental humidity related to the heating of our homes. Never forget this detail if you want to get noteworthy specimens.
Light: they also bear not very bright environments. They do not tolerate direct sun.
Watering and environmental humidity: water abundantly in spring-summer; reduce doses in autumn-winter (especially if the temperature drops a lot), however making sure that the soil is always damp. Keep the humidity very high by placing the pots on bowls containing gravel or pebbles always kept wet and frequently spraying the foliage.
Substrate: composed of soil of ripe leaves and peat, with the addition of sand.
Special fertilizations and tricks: from May to September fertilize every 2-3 weeks. Every year, in March, remove the plant from the pot, remove the dry leaves and, if the plant has grown a lot, replace the pot; otherwise add only a little new peat-based soil and reuse the same pot.
Multiplication and pruning
Multiplication: in March new specimens can be obtained by division of the tufts. In the same period it is possible to proceed with the separation of the stolons, which some species produce in large quantities, and their transplantation into single pots (better if the new seedlings have already developed roots). "Pruning" mother plants at 15-20 cm in height favors the production of stolons. Sowing of spores is only possible for standard species, as hybrids and horticultural varieties are mostly sterile.
Pruning: cut the plants to 15-20 cm. it can be useful to obtain a greater number of stolons to be used to renew the specimens in our possession.
Diseases, pests and adversities
- Leaves that turn brown and become fragile: lack of water and humidity.
- Yellowed leaves: nutritional deficiencies.
- Brown mealybugs: they occur with the formation of brown growths (determined by the small "shell") and giving the plant a blackish and sticky appearance (due to the production by the plant of sugary substances that make it subject to attack by fungi and fumaggini). They are fought by removing them and treating the plant with an anticoccidic product or by rubbing the affected parts with a pad soaked in water and alcohol.