Ferns are an odd group. They lack the color or fragrance of flowers, or the branch structure of shrubbery, trees or vines. Very few turn color in autumn. They provide only green foliage. Yet, as simple as this seems, the generally evergreen foliage that ferns provide is some of the most distinctive foliage that can be found in the garden.
With few exceptions, ferns are richly deep green. Only a few are lighter green or almost yellowish. The leaves, which are known as ‘fronds’, can be soft and papery, or coarse and tough. The fronds of most ferns are pinnately divided (on a central midvein) into neatly arranged leaflets; and many ferns have leaflets that are intricately lobed. Some ferns have leaves with more palmate symmetry. A few ferns actually have undivided leaves.
The Australian tree fern is the largest of the common ferns. It develops a broad canopy of long fronds on top of a trunk that can launch it as high as a two story home. Both the fronds and trunk of the Tasmanian tree fern are shorter and stouter. The trunks are not really stems, but are thick accumulations of roots dispersed through decomposed stem tissue.
The staghorn fern is an epiphyte that naturally clings (nonparasitically) to trunks and limbs of trees. The flared upper fronds collect foliar litter that falls from the trees above, to sustain the roots within. In home gardens, it is popularly grown on wooden plaques, or hung like hanging potted plants, but without a pot.
Some ferns can be grown as houseplants like the classic Boston fern, which cascades softly from a hanging pot. Maidenhair fern is popular for intricate foliage on wiry rachi (leaf stems). Squirrel foot fern has lacy foliage and interestingly fuzzy rhizomes that creep over the edge of a pot.
Since almost all ferns are understory plants that naturally live on or near a forest floor below taller trees, they are generally quite tolerant of shade. In fact, most prefer at least some sort of partial shade. This is quite an advantage for spots in the garden that are too shady for other plants. However, many ferns are more demanding than other plants are in regard to soil quality and watering. They perform best with rich soil and regular watering, and respond nicely to fertilizer.
Highlight: Giant Chain Fern
On the West Coast between British Columbia and Mexico, the largest native fern might be the giant chain fern, Woodwardia fimbriata. In damp coastal forests, it can get taller than six feet, although it is typically about three feet tall and wide in home gardens. The lightly yellowish green fronds generally stand upright and flare outward from the center. The substantial foliage is doubly lobed and lacy. Thick rhizomes spread rather slowly. Established plants are remarkably resilient. They can tolerate almost full sun exposure if watered enough. Those in partial shade can tolerate lapses of watering. However, giant chain fern does not recover too readily from relocation or division.