Ferns can transform a difficult area of the garden, where few other plants will thrive, into an oasis of delicate foliage. Ferns, among the most ancient plants on earth, first appeared about 400 million years ago, long before any flower-bearing plants. Worldwide there are about 1,000 species. The majority are found in the tropics. Of the 360 species that grow naturally in North America, many are concentrated in the north and east, where higher humidity ensures the moisture necessary for fertilization.
Most native ferns can be successfully transplanted into home gardens. Ferns could be used alone in a shady border, mixed species of different sizes, shapes of frond and shades of green. They also make a good foil for shade-loving flowering plants which do well in similar conditions as ferns. Bleeding heart and astilbes blend well with shield fern and osmundas. Wild flowers, such as wild geraniums and violets, add a touch of color to ferns variant shades of green. Columbines and primroses come in a variety of colors and can be interspersed effectively. Some flowering shrubs like the azaleas, add a mass of color in springtime. Probably the best foliage plant to grow with ferns is hosta, with its myriad of color and leaf pattern and leaf texture.
Ferns should be grown far enough apart to prevent fronds from intermingling. Spaces between plants or at the front near the border can be filled in with low-growing perennials, such as bergenias or lily-of-the-valley.
Torenias and wax begonias also make good edging plants in a fern garden. Tuberous begonias, hardy begonias and impatiens can also combine to give a pleasing effect. Daffodils can be used with large ferns, which will cover their untidy leaves after blooming. Tall woodland lilies look very elegant rising from among arching fronds of ferns.
The hay-scented fern and other sun-tolerant ferns do well in nearly full sun. They can be used to cast interesting shadows on large rocks in sunny places.
Many ferns are evergreen and are invaluable for brightening up the winter garden. Shield ferns and the polypodies are particularly delightful when their fronds are edged with frost. In a rock garden the evergreen spleenworts remain bright when most other plants have faded.
To prepare the soil for planting: Dig soil in autumn or spring and sprinkle bone meal over it. Add a 3-inch layer of leaf mold and work it into the soil.
Planting Techniques: Crown-forming Ferns - Remove old frond bases and plant with the crown flush with the surface. (Example: shield and ostrich ferns) Rhizomatous Ferns - Lay the rhizome in a shallow hole, cover with soil and firm. (Example: hay-scented fern and polypodies) Rock Ferns - Remove a stone in the rock garden or dry-stone wall, plant the fern on its side with leaf mold, and replace the stone.