One might not think of ferns as tough plants, but their delicate fronds are surprisingly hardy, especially the native species found in Britain. Even in the winter, their filigree-patterned leaves can be seen adorned with hoar frost. Ferns like hart’s tongue and shield ferns are particularly resilient, adding a touch of lushness to Western hedges and woods. Polypodies and spleenworts also thrive in various habitats, including walls and tree trunks.
Unfamiliar Ferns and Garden Escapes
It’s always exciting to come across unfamiliar ferns growing on walls in towns and cities. Many of these ferns are actually garden escapes that have established themselves in the UK. So, keep an eye out for these unexpected botanical delights.
Native Ferns and Wildlife Gardens
Native ferns are not only beautiful but also valuable additions to any wildlife garden. Frogs, beetles, and snails find shelter among their fronds, creating a harmonious and thriving ecosystem. So, consider incorporating native ferns into your garden to attract and support local wildlife.
Hard Fern (Blechnum spicant)
The hard fern is a dark green fern with tough, leathery fronds. It can be found in woods and moors with acid soils, primarily in the west and north. Unlike most UK ferns, the hard fern is singly pinnate, giving it a sleek and attractive appearance. It has both sterile and fertile fronds, with sterile fronds lying on the ground to absorb energy from the sun, and fertile fronds standing tall.
Maidenhair Spleenwort (Asplenium trichomanes)
This small fern has delicate fronds with rounded leaflets on wiry, black stalks. It can be found on walls, rock faces, and branches across the UK. Maidenhair spleenwort prefers dry habitats and thrives on well-aerated walls. It makes an excellent addition to gardens, with its light green leaves providing a beautiful contrast to the dark stems. Look out for the spores that mature from red to brown under the leaves in summer and autumn.
Wall Rue Spleenwort (A. ruta-muraria)
Wall rue spleenwort is a small fern with dark green fronds and spoon-shaped leaflets. It loves limestone and often grows on old brick walls alongside maidenhair spleenwort and hart’s tongue fern. This evergreen fern disperses its spores in October, and you can consider planting it in garden rockeries as cover for insects.
Black Spleenwort (A. adiantum-nigrum)
This small fern has glossy, triangular fronds with reddish-brown or black stalks. The leaves of the black spleenwort are quite firm compared to other ferns, and it can be found in rocks, limestone, wall mortar, and banks. The spores of this species ripen from June to October and appear as a brownish, orangish aggregation on the undersides of leaflets. Sometimes, the black spleenwort can appear darker green when it grows on the forest floor with little exposure to sunlight.
Rustyback Fern (A. ceterach)
Another small fern, rustybacks are recognizable by their dull green fronds divided into blunt lobes, growing in a characteristic zig-zag pattern up the stem. As the name suggests, rustybacks have rusty scales on the rear of their leaves. During dry periods, the ferns can curl, revealing this brownish side, making them appear dead in winter. However, they quickly recover when exposed to wet weather.
Hart’s Tongue Fern (A. scolopendrium)
This fern can be found in woods, hedges, and walls across Britain, except in the far north. With its strap-like fronds, which are not divided like other UK evergreen ferns, it looks more like a tropical plant. The Hart’s tongue fern gets its name from its resemblance to a deer’s tongue, and the underside of the leaves has tiny marks that resemble the legs of a centipede. These marks are where the spores are stored.
Sea Spleenwort (A. marinum)
Sea spleenwort is a bright green fern with leathery, fleshy fronds that grow in sea caves, rocky walls, and building mortar along the coasts in the west and north. It is one of the few ferns that can survive in salt spray. Spores are released year-round from dashes that cross the undersides of the leaves. Older sea spleenwort plants have elongated fronds and alternate growing leaflets, although they actually grow directly opposite each other on the stem.
Common Polypody (Polypodium vulgare)
Sprouting from rhizomes on walls, hedgebanks, and mossy tree trunks, the common polypody fern has simply divided fronds. It thrives in damp and shaded areas, as well as drier gardens, although it is scarcer in the east of the UK. The leaflets are long and not very tapered, growing opposite each other on the stem. Look for the spore pores scattered on the undersides of the leaves.
Southern Polypody (P. cambricum)
Very similar in appearance to the common polypody, the southern species has broader and more palm-like leaves. It grows in old walls, cliffs, and tree trunks, and is also less common in the east. Out of the three polypodies in the UK, the southern polypody is the rarest species.
Soft Shield Fern (P. setiferum)
The soft shield fern has long, soft, feathery fronds covered in brown scales. It grows among hedges and wooded slopes, mainly in the west and south. This handsome fern provides a welcome green spray of color during autumn and winter months.
Hard Shield Fern (Polystichum aculeatum)
Similar to the soft shield fern, the hard shield fern has more leathery fronds and shiny leaflets. It prefers growing on wooded slopes or near water, with a preference for humus-rich soils and limestone rock. Fronds exposed to direct sunlight appear light green, while those in shady crevices remain dark green.
Wilson’s Filmy Fern (Hymenophyllum wilsonii)
Wilson’s filmy fern is a small and creeping fern with translucent fronds that are just one cell thick. At first glance, it may resemble a tuft of moss, but it is actually part of the fern family. The dark veins running to the tips of the leaves are distinctive, but it’s easy to overlook as it grows among clumps of moss. Look for it in shady woodlands, especially in the ‘Atlantic rainforest’ region of the UK with high rainfall and low temperature variation.
So, the next time you spot a fern, take a moment to appreciate its beauty and unique characteristics. Whether it’s a native species or a garden escape, ferns add a touch of elegance and serenity to any environment.
All illustrations by Felicity Rose Cole.
