Fabulous Ferns
When we planted our cool, shady garden 9 years ago, I added some ferns without knowing much about them except that they liked cool and shady. They are so little trouble I almost forget about them. Ferns add a delicate, feathery green that contrasts and blends well with our other shade-loving plants. Then, last Saturday, I attended a Master Gardener workshop on ferns and was stunned to discover another fascinating horticultural universe. My head too full of information, I returned home to my garden and garden books to sort out what I had learned and to identify the familiar ferns in my garden. Let me share some useful information.
Ferns are one of the oldest living plants (400 million years), so old their reproductive system (spores) evolved before seeds. To have outlived dinosaurs, they are survivors and are adapted to various climates and conditions in addition to cool and shady. For our purposes (our local gardens), it is most useful to know a few facts about ferns. Some are deciduous; some evergreen. Most are ignored by garden pests like squirrels and deer. They do not flower. While we are familiar with their basic shape– green fronds emanating in a circular fashion from a central core at ground level—we might not be aware of the considerable variety in the color and design of the fronds. Some, with deeply cut leaf patterns are extremely delicate and feathery. Their compound leaf blades are defined as pinnate, bipinnate, or tripinnate, depending on the division of the leaflets. At the workshop, we took spores of ferns, and planted some dried spores in a pasteurized soil mixture, a complex and taxing process that helped me appreciate that ferns reproduce at all.
Our woods and gardens are full of a variety of ferns. I’ll begin with 2 at the Inverness Library, both natives. Woodwardia fimbriata (GIANT CHAIN FERN in the Deer Fern family) is the large (4 – 5 feet), evergreen fern that surrounds the library’s front deck. According to Margo Wing, these plants are old, predating the reconstruction of the Gables house by decades. They were moved during the construction in 1984, replanted and have been thriving since. Some of their long fronds turn brownish in winter and can be cut way back, making way for new ones each spring. The garden also attracts volunteer LADY FERNS (Athyrium felix-femina), a mildly invasive, very attractive, deciduous fern that, if left alone, will grow to 4 feet and spread. Removing an old, established Lady Fern is a tough job. Unattractive in winter, their particularly lacy, delicate fronds are pretty the rest of the year.Another Athyrium, PAINTED FERN, grows by my front gate. Also called Japanese Painted Fern, it has the same lacy fronds as the Lady Fern, but is only 15 inches high and is streaked with silver with a burgundy stem. Very colorful and well behaved. Deciduous, it disappears in winter. I have dwarf mondo grass growing around it, so its winter absence is not noticeable.
Maidenhair ferns, also natives, come in two forms: SOUTHERN MAIDENHAIR (Adiantum capillus-veneris) appears delicate and fragile, with small fan-shaped leaflets on a thread-like stalk, to 1 foot or so, but will spill over containers or walls. An elegant, small-scale fern, it thrives near our gate in the shade of a podocarpus. It is deciduous like its cousin, the WESTERN FIVE-FINGERED FERN, which is far tougher than its 15 inch, delicate foliage indicates. We have some that have naturalized on a shady bank, totally ignored and seldom watered.
Polypodium californicum (CALIFORNIA POLYPODY) is another native, deciduous fern. It is dormant in summer, unfurling its 4 to 12-inch bright green fronds with the first fall rains. A pretty light green, it does well in sun or shade in West Marin and requires little water. One of its pretty cousins, Polypodium scouleri, is evergreen with upright leaves to 6 inches.
The one fern left unmentioned is the ubiquitous, evergreen WESTERN SWORD FERN (Polystichum munitum), so familiar in our woods and invasive in our gardens. Vigorous, a bit of work to keep trimmed, but valuable in dry shady places.
Ferns are marvelous additions to our gardens, contributing grace, contrasting foliage, and a serenity reminiscent of our nearby woods.