Even though the very second plant I ever owned was a fern called 'Fluffy Ruffles' given to me by an admirer (the first being a spider plant detached as a 'pup' from a plant growing out of a teapot on the kitchen table of the share house I lived in during the 1970s), I have never really understood ferns. Well, the reality was the poor old Fluffy didn't last very long at all on the hot, west-facing windowsill of that house, and my knowledge of ferns didn't improve much after that. However, in recent times I have become fascinated with ferns, as part of a general interest in plants that grow well in the shade, now that I know that's where they belong. Probably few other plants are as well known for their shade tolerance as ferns, as they seem to be able to survive in some of the darkest parts of the garden - and some can even apparently grow in caves!
The world of ferns (known as the Pteridophytes) is vast. There are around 13,000 species of ferns. There is definitely something quite mysterious and fascinating about them. For a start, they don't bloom at all. They are very primitive plants in the sense that they were one of the first types to evolve and they use spores, usually on the back of their fronds, as a way of reproducing. They also are a bit bewildering because so few ferns are sold in nurseries with a proper name label - also, the names themselves can be vexed and unresolved by botanists! I've just had to gradually learn about the ones I grow through trial and error. I have had quite a few ferns just 'appear' in my garden, sometimes growing in brick walls and steps, so identifying these has also been a challenge at times.
There are tiny ferns and enormous ferns. The leaves of ferns are quite diverse, but all are attractive. The leaf blade can be simple but is more usually divided into leaflets and arranged like the plumes on a feather (though there can be other shapes). Sometimes the leaflets are further divided into more leaflets. The lacy, feathery appearance of ferns adds a softness and lightness to a shaded garden area, and they provide a wonderful contrast to bolder foliage plants such as Colocasia, Aspidistra and Zantedeschia (as pictured above). The smaller ones also can create a serene woodland atmosphere when grown with some of the perennials that do well in shady Sydney gardens, such as Saxifraga stolonifera, Geranium macrorrhizum and hellebores, and small shrubs such as Ruscus.
Most ferns are green (of varying tints and hues), but some are beautifully marked in hues of silver, pink and orange. In some cases, the new growth emerges in a different colour, then ages to green. Some have a glossy surface whereas others are matte in texture. The unfurling of the new leaves in spring is very thrilling. Many have a distinct crown from where all the fronds emerge, but others have running rhizomes and can be invasive - think fishbone fern and asparagus fern! Most are evergreen but some are herbaceous. There are ferns for every climactic zone. Some are aquatic, many are terrestrial and quite a few others are epiphytic. In Sydney we can grow some cold-hardy ferns as well as some of the more frost-sensitive ones, for those who have mild winters.
Some cold-hardy examples are Cyrtomium falcatum (ht 60-90 cm), the holly fern, which has bold, glossy, spiny leaflets, and makes a wide clump, spreading by rhizomes. The mother shield fern (Polystichum proliferum, ht 1 m) is a native terrestrial fern that tolerates cooler temperatures well and also copes with dry spells better than most ferns. Mature plants form a large clump and have a thick rhizome densely covered with dark brown scales and these can become almost trunk-like. Small plantlets form on the tips of the fronds and these take root when they weigh the frond down until they touch the ground. Another cold-hardy fern is silvery, pink-tinted Athyrium niponicum 'Pictum' (Japanese painted fern, ht 30 cm). It will grow in full or part shade, but part shade gives more colour to the foliage. It is deciduous - every year I forget this and think I have lost it, but it reemerges in September.
Most of the warm-climate ferns that thrive in Sydney are native plants that come from rainforests or mountain gullies or grow beside creeks. Many are epiphytic, growing on stumps, rocks and trees (though they will also grow in well-drained soil and in pots), and one of the most dramatic is the bird's nest fern (Asplenium australasicum), which has wide, undivided fronds up to 1.5 m in length that unfurl from its centre. It makes an outstanding feature plant and needs to be given space around it so that it isn't swamped by other plants. Lower-growing ferns with intricately divided foliage juxtaposed nearby can provide textural variation that looks very pleasing. Two other sculptural-looking epiphytes are the stag horn fern (Platycerium superbum, though this name is unresolved, ht 90 cm - 1.8 m) and elk horn ferns (Platycerium bifurcatum, ht 1 m). They have neatly folded sterile leaves that wrap around their roots and catch the organic litter that sustains them and pendulous fertile fronds that are forked like the antler of a deer. They will grow on rocks, trees and stumps but are often attached to boards that are then hung on shaded walls, trellises or fences - a few mature specimens of these together makes an imposing statement. Microsorum species also have bold, divided foliage that is quite dramatic, often with decorative raised 'pimples' along the length of the fronds. Kangaroo fern (the one I grow, pictured at the start of the blog) is, I think, Microsorum pustulatum (ht 50 cm). It can form a very robust clump even in quite dry soil and thus is an excellent filler. I'd love to know the proper name if I have this wrong here!
Finer-cut, warm-climate native ferns that provide a textural contrast to these bolder forms include tall hen-and-chicken fern (Asplenium bulbiferum, ht 1.2 m) with its lacy fronds and plantlets that develop at its tips; the prickly rasp fern (Doodia aspera, ht 20-40 cm), with gorgeous pink or reddish-orange new growth; and the fishbone water fern (Blechnum nudum, ht 80 cm, lush and shiny leaves). One of the best known is the dainty maiden hair fern, such as the common form seen on many a bathroom sink (Adiantum aethiopicum, ht 30 cm), which spreads when happily sited, and the 'giant' version (Adiantum formosum, ht 80 cm). Native brake ferns (Pteris species) include the tender brake (Pteris tremula, ht 1.5 m) and the jungle brake (Pteris umbrosa, ht 1 m). A very pretty one called the variegated brake (Pteris cretica 'Albolineata', ht 45 cm) comes from tropical and subtropical Asia, Africa and Mediterranean countries, and has long, pencil-thin fingers of leaves, with silvery-white central bands. I find it self-seeds very readily in my garden.
All of these ferns will grow in partial or heavy shade. Generally speaking, ferns enjoy moist yet well-drained soil rich in organic matter, as in their natural environment, but once established they can tolerate quite a bit of dryness, especially if they are mulched and given the occasional drink in hot weather. They do like humidity, so a spray over their leaves with a hose every so often is appreciated in summer. Ferns make excellent subjects for pots and hanging baskets in shade.
The wonderful fern house at the Royal Botanic Garden, Sydney is well worth a visit to see many ferns - well labelled and grown superbly; a trip there is on my wish list when I can finally leave my LGA.
19 Sep 21
Meet some of the ferns that grow well in Sydney,
A garland of daisies
12 Sep 21
Daisies seem to epitomise spring and there are lots to choose from for Sydney gardens.
05 Sep 21
September sees some beautiful and easy-going shrubs come into bloom in Sydney.
Borage and kin
29 Aug 21
The herb borage has some easily grown relatives.
22 Aug 21
Many plants need rejuvenation after a few years.