The Casual Gardener: Fantastic ferns
They have no flowers or fruit but John Manley argues that's no reason to ignore the appeal of ferns
I LIKE to think the notion that a garden with more flowers is somehow better than one with fewer is thankfully on the wane. This approach found its greatest expression in old-style planting schemes that use bedding en masse – blasts of primary colour whose impact is immediate and unsubtle then fades unspectacularly as the year advances.
Flowers do of course play an important role in the garden, both from the point of view of aesthetics and biodiversity – they are the stars of the summer garden, creating often breathtaking beauty while ensuring it is busy with insect and bird life. However, having a variety of foliage and plant types is equally important, especially those that bring character and atmosphere.
Ferns are plants that easily fit this bill. They are not conventionally beautiful in the same way as daffodils or roses but their allure is equal and their back story arguably more interesting. They tend to inhabit the cool and shaded recesses, preferring moist humus (de)composed of the well-rotted predecessors of the canopy above. Some, however, such as the Shuttlecock fern (Matteuccia struthiopteris) and the tree fern (Dicksonia antarctica) can tolerate and even thrive in full sun.
Ferns were one of the first plants to colonise the Earth, with fossils showing they existed more than 350 million years ago. They were abundant during the Carboniferous period – when coal was made – and some species from that prehistoric era prevail today, though you won’t find tree ferns reaching 30 metres or horsetails measuring 15 metres, as existed back then.
Ferns are found everywhere in the world bar those places that are covered by ice all year round. They range in size from the diminutive water fern Marsilea quadrifola to the towering tree ferns of the tropics (5-10 metres). There are also ferns that climb, with Lygodium japonicum or Japanese climbing fern among the more obscure choices for gardeners. Few tend to be invasive but Pteridium aquilinum – what you and I know as bracken – is among the most common plants on the planet and the bane of many Irish upland farmers.
The Victorians popularied ferns as an ornamental plant, growing them inside miniature glasshouses or terrariums. This was done in part out of necessity, as the air in urban Britain around 150 years ago was too toxic due to high levels of industrial pollution.
For the more ambitious rural gardeners of the time – those with more room and resources at their disposal – specially landscaped areas furnished with moss-covered tree stumps and stones, known as ferneries, became a fashion.
Ferneries are still a thing with some gardeners though the plants are deployed more widely alongside other woodland flora rather than exclusively – the atmosphere of the fernery lives on, however.
Most ferns are happy in any moist, well-drained, shady site in well-dug, humus-rich, neutral to alkaline soil. However, those such as the royal fern (Osmunda regalis), require neutral to acid soil.
Taking ferns from the wild is against the law, though it is possible to take a small section of the plant’s root without disturbing the entire fern – in moderation, of course.
Always improve the soil before replanting by incorporating organic matter, such as garden compost or leaf mould, adding water o the roots.
For moist soils, select deciduous ferns such as the western maidenhair fern (Adiantum aleuticum) and the brittle bladder-fern (Cystopteris fragilis) or evergreens and semi-evergreens such as the hart's-tongue fern (Asplenium scolopendrium) and the golden shield (Dryopteris affinis).
If sited correctly they should require minimal attention and usually only need pruning when a mild winter fails to make the fronds die back completely.