by John Richmond
Every garden needs contrasts of form and foliage in its plantings. For me, one of the prime suppliers of this contrast lies with ferns. Most have a grace and delicacy that adds interest to any planting scheme. None flower, but what they lack in colorful blossom they make up for in foliage interest.
Ever since I started to garden I've grown ferns. In 1974 I moved to Plymouth in South West England. I was used to the plants that grew around my home on the east coast of England, an area where 25 inches of rain in a year was normal. Plymouth enjoys over 50 inches of rain a year. Suddenly, I was surrounded by plants that grew in the presence of abundant moisture in the air and the ground. From knowing one or two common, hardy, ferns I was faced with numerous new - to me - species. It sparked an interest that developed as I got to know the garden worthy varieties. I may not have the room to grow the extensive collections of the fern specialist - but I can still fit in a few of the more interesting.
Among my favourites are the hardy maidenhair ferns. Adiantum venustum comes from the Himalayas, likes nothing better than a cool, lightly shaded site in moist, humus rich soil, and runs around mildly when suited. Deciduous, the leaves emerge bronze in the spring and remain fresh and green until they wither with the chills of autumn (fall). Unlike the similar maidenhair ferns grown as houseplants, this slightly smaller relative is hardy to at least Zone 7 but can thrive in colder climates with some amount of winter protection. Even hardier to zone 3, is its close relative, the bird's foot maidenhair, Adiantum pedatum, some varieties of which come from as far north as Alaska and the Aleutian Isles. My own favorite is the clone 'Roseum', with rich pinkish red young fronds, a spring shade that adds lustre to the early year.
Once again, this plant needs light shade and moisture in the air and soil. This is a common theme with ferns. Most come from shaded woodland or, if they grow in the open, enjoy cool root runs among rocks on hillsides or in moisture rich soils by lake or riverside. In the garden they enjoy similar conditions. I site most of my ferns amongst other plants in the shade of walls and taller shrubs or in the artificially moist soil round my small pool. With some ferns, however, placement becomes irrelevant. They will grow almost anywhere.
One of my most elegant ferns, which has multiply divided fronds that create an airy, lacy effect, is a variety of Polypodium vulgare called 'Cornubiense'. The species will thrive in the dry, rooty soil under the most demanding of forest trees. In my local woods it even grows on the branches, sharing a perch with mosses and lichens. This is a tough plant, hardy to Zone 3, and its far more elegant offspring shares this tolerance of adverse conditions. I grow it in dry shade on the edge of a retaining wall and it is spreading slowly to form a carpet about 12 inches / 30 cm high. Some fronds come plain and I remove these to leave only the most finely dissected.
A little less tolerant of drought but still pretty hardy (Zone 5) is Dryopteris affinis. This is a classic fern, with elegant, arching fronds arranged in a shuttlecock formation from the central crown. The species grows wild in my native woods, brightening spring with the freshest of yellow-green growth. I grow a variety called 'Cristata The King', where each frond division is further divided at the end in an elegant tassel. My plant is young, and the fronds have still to reach their full 3 foot / 90cm expansion, but already it shows promise for the future.
Equally tough is the similar looking, zone 4 hardy, Polystichum setiferum. This turned up in the garden, sowing itself in the way of ferns from a wind borne spore that alighted in the pot of a Yucca. Full sun, occasional drought, the reflected heat from the wall, it copes with them all. I intend to move it. In it's current position it will only remain stunted, and such a beautiful fern deserves better. There are numerous varieties of this evergreen fern, some with extremely divided fronds, but I still enjoy the simple foliage pattern of the species. It is ideal for growing in a mixed planting of hostas, siberian iris, and other good foliage plants.
Many ferns have a very similar appearance, with an arching shuttlecock of growth from a central crown. No hardy fern does this better than Matteucica struthiopteris, the Ostrich feather fern. Hardy to zone 2, it needs moist soil and can run about in good conditions, putting out long runners from the parent to produce daughter plants 2 or 3 feet away. When it runs beyond the allotted space, these can be removed and replanted. I may well have problems in years to come - but in the meantime I'm going to enjoy the symmetry of this most elegant of plants.
Two of my other ferns are never going to cause similar problems. Athyrium otophorum 'Okanum' is not particularly hardy but survives winters unprotected in my mild, zone 8 climate. A small fern, I grow it for the delicate silvering on the leaves. Even more highly coloured is the Japanese painted fern, Athyrium nipponicum 'Pictum'. Here the fronds are distinctly silvery, with red tints on the black midribs. Altogether one of the most spectacularly coloured ferns I grow. But it must never dry out. The fronds wither at the slightest provocation - as I found when I came to photograph my plant recently. We'd had a few dry days, it ran short of water, and the plant I'd nurtured to get that perfect shot was just a mass of withered fronds. It's now recovering - but I'll have to wait till next year for the photograph.
I might have to wait a hundred years for the best photograph of the final fern I'm going to write about. I have a plant of the hardiest of tree ferns, Dicksonia antarctica. It will, eventually, form a stout trunk, topped with a crown of fronds extending to 20 feet / 600cm or more. My baby is less than a foot tall. Over the next ten years it should grow slowly to eventually rival plants that would cost me the equivalent of 2-300 dollars US rather than the 2 dollars it actually cost me in a plant sale. With some ferns, it pays to be patient.
About the Author John Richmond is a keen gardener who lives and works in the South West of England. He has a scientific background as a professional ecologist. He has written occasional articles for gardening and other magazines in Britain since 1984, specializing in garden wildlife issues and hardy plants. Correspondence from other gardeners is always welcome.