How to Grow… Ferns
Brimming from the borders of your garden, ferns can create a tropical labyrinth of green in even the shadiest of gardens
7 August 2018
With their fascinating feathery foliage, vibrant green hues and interesting textures, ferns are, quite simply, fabulous! Not only do they look the part, but they’re relatively easy to grow, are invaluable shade plants, demand very little maintenance and there's even a range of evergreen varieties to choose from to keep your backyard looking lush all year round.
There is a diverse array of ferns for gardeners to choose from, available in all manner of shapes and sizes and all well suited to growing in shady locations such as underneath tree canopies or in the protective shadow of a garden wall or outbuilding. Ferns are most commonly spotted in bushland growing in shady ravines or carpeting the forest floor, with over 400 species found in Australia.
What are they?
The term ‘fern’ refers to a flowerless vascular plant in the Pteridophyta family that does not produce seeds but instead reproduces by spores found in clusters on the underside of the leafy fronds. When the spores mature, they are released from the cases and get dispersed by the wind where they can then germinate in suitable soil. Ferns are part of an ancient family of long-lived plants predating even the dinosaurs. They thrive in areas of moist soil, which allows fertilisation to successfully take place.
Whatever fern species you choose, they’re sure to add a fresh dimension to your garden with their eye-catching fronds and spirited form. With very little threat of pest problems, apart from the odd slug, ferns are a great all-rounder for your yard with everything from tree and ground ferns to climbers and pot plants available to grow relatively easily. Despite popular belief, ferns do not need lots of water and deep shade to survive. In fact, they will be quite happy in a sheltered spot of the yard in damp or semi-arid composted soil with good drainage – a layer of shredded leaf mulch will help to retain moisture. Ferns notoriously like shade but many species prefer light or dappled shade to deep shade, and some, like the Little Aussie Larrikin, require full sun. However, be aware, as most ferns cannot tolerate direct sunlight or dry heat.
Ferns are very forgiving plants able to withstand periods of drought as well as bouts of hot and cold weather. The frequency of watering depends on the fern species you have selected, though most will be happy with a sprinkling every couple of days in dry, hot weather, and less often in winter. As ferns naturally grow slowly, don’t be tempted to speed them up by overfeeding. An occasional application of fertiliser is all they’ll need for a vitamin boost, but most will do just fine without any supplementing.
Also known as holly or shield ferns, the Polystichum species are among the hardiest ferns you can grow, made up of both evergreen and deciduous species sporting dark green feathery fronds with toothed leaflets. These ferns do best growing in full or dappled shade in humus-rich soil with excellent drainage.
The soft tree fern is a beautiful, reliable fern ideal for planting in a shady spot in the backyard. The slow-growing species boasts a sturdy trunk and long fronds perfect for providing additional shade in the garden. The species is very capable of withstanding dry spells and requires little maintenance to keep it looking at its best. Suitable for growing in a container or straight from the soil, the soft tree fern is best grown in moist, loamy soil in sub-tropical, warm and cool climates.
This species, also known as autumn fern or Japanese wood fern, boasts triangular leaves and a striking copper-red foliage in spring that transforms to a bright glossy green hue as it matures. An evergreen variety, the autumn fern thrives in partial or full shade in moist, well-drained soil. Water can be provided as needed, as long as you ensure the soil never becomes overly dry.
This soft, lacy evergreen species, most commonly known as the maidenhair fern, is suitable for growing both indoors and out, displaying a delicate apple green foliage. Usually grown as a smaller plant, the maidenhair fern requires a regular supply of water to stay looking good, as at the first sign of drought it will turn brown – though this doesn’t mean it’s dead, so water it first before throwing in the towel. Requiring deep shade, humidity and shelter from the wind, this plant is very versatile, often grown in hanging baskets and in rockeries for added interest in the garden.
Blechnum gibbum ‘Silver Lady’
This beautiful rosette fern will conjure up images of a jungle oasis when planted out in your backyard. Excellent for a shady spot with consistently moist soil (a slightly acidic, loamy soil is best), or kept indoors as a pot plant, this species of fern likes humidity, so use the misting function on your spray gun to keep it extra happy. Unlike many other species, the silver lady fern will grow quite quickly in the right conditions, as long as it is grown in an area free from frost and direct sunlight.
This unique plant, usually referred to as hare’s-foot fern, features furry prostrate stems that creep above the surface of the soil, supporting the plant’s wiry stalks from which small lacy leaflets shoot out. Frequently grown in hanging baskets or as a houseplant, this species can take on a spider-like appearance with its sprawling fleshy rhizomes that creep above ground to absorb moisture for the plant. The hare's-foot fern, like most plants in the fern family, prefers growing in shade in moist, well-composted soil with good drainage.
Good news! Ferns are low maintenance. Whether you have a courtyard or an acreage, ferns can transform any outside space and there are literally thousands of species to choose from. One of the most important maintenance tasks to keep ferns happy is to find the balance between keeping the soil moist and overwatering. Ferns do require moist soil, though won’t be happy being waterlogged, so feel the soil and keep an eye on the weather to achieve a happy medium.
Often, if the fronds are discoloured or wilting, it is due to lack of water. Mulching around your ferns without letting the matter touch the base of the plant is an excellent way of retaining moisture and may even reduce the need to water as often.
You don’t need to cut back a lot of species of fern, their fronds actually form a natural protection for the plant, but you can clean up dead fronds and trim them back to keep them tidy. It is recommended to wait until after their spores have been released before you start cutting ferns back – winter or early spring is best.