Ferns and Selaginellas: In almost every garden, there will be areas, particularly those facing north or north east, which are shaded or partially shaded, not suitable for growing most of the garden plants. However, in such situations ferns can be grown successfully, as many of them are shade loving except some which can tolerate sunshine.
They are distributed all over the world but most of them are natives of the warm and humid tropical regions. There are about 1000 indigenous species in India. In the hills, ferns are found to grow in nature in well rotted spongy carpet of leaf humus. They are either terrestrial or epiphytic, the former growing in soils rich in humus and the latter on branches of trees. Ferns vary much in size, form and growth habit. There are tree ferns (Alsophylla, Cyathea), about 12-24 m tall or the minute moss like plants, less than two cm high.
Also there are tiny water ferns (Azolia and Salvinia) which are only 2-3 cm high covering the water surface and the ferns that climb on supports (Lygodium, Paraleptochilus). The form and size of foliage, commonly known as fronds, vary in different species. The fronds may be simple and entire (Asplenium nidus), pinnate, much divided, (Nephrolepis exaltata, Adiantum peruvianurn), or formed like a staghorn (Ratycerium bifur-caturn).
Ferns are propagated from spores which are produced in small dark brown cases known as sporangia on the back of the fronds. Spores are sown in a shallow earthen pan containing a layer of broken pieces of brick and filled with coarse sand mixed with soil and leaf mould in equall quantities. The potting mixture is levelled and watered lightly before the spores are broadcasted over it and glass or a polythene sheet. The covered with a pane of pan placed in a saucer containing water is kept in shade. The spores germinate in about 2-3 weeks. Another common method of multiplication is by division of roots of old plants.
Planting in Pots and Repotting:
Medium-sized pots of 15-22 cm are suitable for planting ferns. The compost for ferns contains one part coarse sand, two parts leaf-mould, one part soil, one part charcoal (small pieces), one part crushed lime mortar or lime concrete and few small pieces of broken brick. While planting due care should be taken to keep the crown of the fern above the soil. The plants require frequent watering during summer. During winter one should keep the plants in the verandah in a sheltered place to avoid injury due to severe cold. Similarly, fern should be placed in a shaded place during summer.
Ferns are usually kept in a fern-house which is a structure erected with the help of angle irons or wooden posts and covered with wire-netting and light creepers grown round the sides. The roof is covered with a light thatch or mat or nylon-netting so that it does not provide a dense shade. Occasional application of small quantities of crushed lime concrete or mortar and a pinch of bone meal during rainy season is beneficial to plants.
The dead fronds may be removed frequently and ferns should be repotted during the early rains when new growths appear. A little bone meal and crushed limestone may be mixed with the soil when the plants are repotted. Liquid manure is also useful.
The most commonly grown ferns are Adiantum, Asplenium, Btechnum, Davallia, Gymnogramina, Lygodium, Nephrolepis, Osmunda, Platycerium, Polypodium and Pteris. There are several species in each.
Adiantum (Adiantaceae): The Maiden Hair Fern fronds (leaves) delicate, simple or divided into fan-shaped segments, leafstalks black or purplish in colour, loves shade, suitable for pot culture and hanging baskets.
Asplenium (Aspleniaceae): Fronds simple or finely divided. The common Bird’s Nest Fern, A. nidus has glossy green long undivided fronds in a cluster.
Blechnum (Blechnaceae): A dwarf tree fern with divided fronds.
Davaltia (Davalliaceae): Creeping rhizomes, with divided fronds.
Gymnogramma (Polypodiaceae): Fronds finely divided, under surface covered with white or yellow powder.
Lygodium (Polypodiaceae): Climbing fern with finely divided fronds.
Nephrolepis (Nephrolepidaceae): Runners or stolons with pinnate fronds.
Osmunda (Osmundaceae): Pinnate fronds, plain or crested.
Platycerium (Polypodiaceae): The Stag-horn Fern. Fronds broad, divided, resembling the horns of a stag. Epiphytic, grown on wood logs or in hanging baskets.
Potypodium (Polypodiaceae): Fronds simple, undivided, strap-shaped, leathery.
Pteris (Pteridaceae): Fronds divided, many with a central white band in the pinnae and also variegated in some cases.
The hardy species suitable for growing in the plains include Adiantum capillus-veneris (Maiden Hair Fern), A. peruvianum, A. ciliatum (A. caudatum), A. cuneatum, A. tenerum, Asplenium nidus (Bird’s nest Fern), Blechnum occidentale, B. spicant, Cheilanthes argentea, C. farinosa var. sulphurea (Golden Fern),
Crytomium falcatum (Holy Fern), Cyclosorus papyraceous, Davallia bullata, D. solida fijiensis, Diplazium. esculentum, Gymnogramma chrysophylla, Lygodium scandens, L. circinatum, Nephrolepis cordifolia (Sword Fern), N. exaltata (Ladder Fern),
N. exalata var. bostoniensis, N. dufii, N. furcans, Onychiurn Japonicum, Osmunda regalis (The Royal Fern) grows best in hills.
Platyceri alicome (Stag-horn Fern), P. grande, P. bifurcatum, P. wallichii, Poly-podium aureum, P. vulgare, P. nigresceus, P. wallichianum, Pteris cretica (The Brake), P. cretica var. albolineata, Polystichum squarrosum (Hard Shield Fern).
Ferns Suitable for Hanging Baskets:
Adiantum. caudatum, Blechnum spicant (B. bereale), Davallia solida fijiensis, Lygodium scandens, L. circinaturn Microsporium scolopendria (Syn. Pleopeltis phymatodes).
Lygodium scandens, L. circinatum. Epiphytic ferns Davallia solida fijiensis, D. bullata, Platy alicorne, P. grande, P. bifurcatumn P. watlichii, Asplenium spp., Microsporium lucidum, M. punctatum.
For damp and marshy places:
Ceratopteris thalictroides (Water Fern), Doryopteris ludens
For water pools or ponds:
Ceraspteris, Salvinia, Azolla.
The selaginellas are allied to ferns but closely resemble the moss and hence commonly known as the Creeping Moss or the Club Moss. The plants are dwarf with tiny, scale-like green leaves and trailing stems and form a carpet or ball of emerald green. They are shade and moisture loving and can be grown in soil containing gravel. The plants are suitable for growing in rockeries and in pans or troughs.
The commonly grown species are, Selaginella laevigata, S. caulescens argentea, S. emmiliana, S. krausiana, S. erythropus, S. apus, S. africana, S. serpents, besides many other species.