Ferns are the quintessential shade plants. Their graceful, arching fronds conjure up images of shaded retreats and cool walks by wooded streams. Growing ferns in the deepest, darkest woodland is most natural beause of the moist soil and even standing water. However, not all ferns are limited to the shade. Marsh fern, cinnamon fern, and bracken fern grow in full sun.
Growing Ferns In The Landscape
Use large ferns as foundation plantings along with or instead of shrubs. Plant them along fenes or walls to break up the flat expanse. They hide the "bare ankles" of sparse shrubs or perennials. Large hostas and ferns will add interest to a shaded spot. Mass plantings of ostrich ferns and osmundas are very effective for filling bare spaces or adding depth in the shade of tall trees. They also form a perfect backdrop for annuals and perennials.
Use medium-sized ferns such as New York fern, lady fern, and maidenhair fern in combination with spring flowers. Their unfurling fronds are a beautiful complement to spring beauty, wild blue phlox, and others. Fronds will fill in the blank spots left when wildflowers and spring bulbs go dormant.
Try ferns along the border of a shaded walk to define the path, or ferns with creeping rhizomes on a slope to hold the soil. Mix textures and add evergreen ferns such as wood ferns and Christmas ferns for late-season and winter interest.
Crown-forming ferns like interrupted fern and cinnamon fern have a graceful vase shape and make excellent accents alone or in small groupings. They grow slowly, so they won't take over the garden like some running ferns such as hay-scented ferns. Plant rampant growing ferns where they can spread to form groundcovers and fill in under shrubs. For low, wet areas, chain ferns, osmundas, and marsh ferns are stunning. Combine them with the spiky foliage of yellow flags and arrowheads.
Since foliage is the fern's major attraction, consider the color and texture of the fronds. The most colorful garden fern is the Japanese lady fern, Athyrium niponicum. Its hybrids and cultivars, including the many cultivars of A. n. 'Pictum', Japanese painted fern, may have fronds that are gray, blue-gray, gray-green, gray-white, or seemingly variegated with colorful burgundy midribs. (In fact, Athyrium niponicum 'Pictum' was considered so outstanding that it was named Perennial Plant of the Year for 2004 by the Perennial Plant Association.) All of these but the gray-green cultivars look great with blue hostas and heucheras with garnet or purple foliage or gray leaves with garnet veining (Heuchera 'Palace Purple' is a well-known purple-leaved cultivar). The explosion in heuchera breeding has also produced cultivars with gray-green foliage, some with garnet veining, that combine beautifully with the gray-green cultivars of Japanese painted fern; add green or green and white hostas for textural contrast.
Related: 10 Hardy Houseplants Anyone Can Grow
Japanese lady and painted ferns aren't the only ones that offer color and shine to the shade garden. Chartreuse-colored interrupted fern and maidenhair fern combine well with dark ferns and other foliage. The coppery new fronds of autumn fern and its orange-red cultivar 'Brilliance' add warmth to shady sites and look lovely with chartreuse-leaved hostas, heucheras, and tiarellas, as well as heuchera cultivars with coppery foliage. The shiny fronds of ferns such as autumn fern, deer fern, and hart's-tongue fern glisten in filtered sunlight.
Preparing The Soil
Growing ferns generally requires rich, moist soil with extra organic matter. Some require a drier, less-fertile soil. If growing ferns hasn't been successful in the past, have your soil tested by your local extension service or a soil-testing lab to soil fertility and pH. Some ferns are extremely fussy about pH.
Related: Understanding pH
For large and medium-sized ferns, dig the planting area deeply (at the very least, turn the soil to a spade's depth). Plant smaller ferns such as Japanese painted fern as you would any perennial. Sprinkle on organic fertilizer, if needed, when you add soil amendments.
Buying + Planting Ferns
Garden centers offer a few ferns, but you can find more through nursery catalogs and sites that specialize in perennials, shade plants, or ferns. No matter where you buy, make sure plants are nursery propagated, not collected from the wild. Large plants at low prices usually mean wild-collected plants. Don't be afraid to ask for the vendor's sources.
Plant ferns in fall or early spring. Garden-center plants will be potted, but mail-order plants are likely to arrive bareroot. Remove potted plants from their containers, cutting the plastic if necessary. Very carefully score the root ball with a sharp knife. Make three to five shallow cuts lengthwise down the root ball. This breaks up the solid mass of fibrous roots that often forms along the container wall. Plant the fern at the same level at which it was growing in the pot. Planting too deeply will kill plants with single crowns.
Set bareroot plants with creeping rhizomes (underground stems that produce both roots and fronds) 1/2 to 1 inch below the surface. Large rhizomes can be planted deeper. Set single-crowned ferns like osmundas and ostrich ferns with the crown above soil level. Place the upper part of the rhizome above the soil surface, with the crown 3 to 5 inches above the soil, depending on the plant's size. Finally, don't plant too thickly, since most growing ferns spread rapidly.
Ferns are a carefree group of plants. Mulch with shredded leaves or bark to help control weeds and conserve moisture. Ferns never need staking, pinching, or pruning. You may have to remove an occasional damaged frond, but that and watering during dry periods while the plants are getting established about sums up the care requirements for ferns during the growing season.
Each spring, remove last fall's leaves from the fern bed, shred them, and return them to the bed. Clear the bed early to avoid damage to emerging fiddleheads. Don't rake the beds, or you may damage crowns and growing tips. You won't need fertilizer if you leave the mulch to rot into the soil.