Polypody, Adders Fern, Golden Maidenhair Fern, Wall Fern, Common Polypod Fern
Polypodium vulgare
Family: Polypodiaceae
What it is like
Form: Irregular or sprawling, Rounded, Upright or erect.
Polypodium vulgare is an evergreen Fern growing to 0.3 m (1ft) by 0.3 m (1ft in) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 3. It is in leaf all year. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in heavy clay and nutritionally poor soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in full shade (deep woodland) or semi-shade (light woodland). It prefers dry or moist soil.
Height (m): 0.3
Where it is found
Rocks, walls and trees, as well as on the ground, in a variety of habitats but especially in humid shady conditions.
All of Europe, the Mediterranean, temperate Asia and eastern N. America.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Root. Very sweet, it contains sugars, tannin and oils. It is used as a liquorice adulterant. The root has a unique, rather unpleasant odour and a sweet (cloying) flavour at first though it quickly becomes nauseating. The root contains 15.5% saccharose and 4.2% glucose.
Root: includes bulbs, corms, tubers, rhizomes etc.
Medicine
Rating: 3
Polypody stimulates bile secretion and is a gentle laxative. In European herbal medicine it is traditionally used as a treatment for hepatitis and jaundice and as a remedy for indigestion and loss of appetite. It should not be used externally since it can cause skin rashes. The root is alterative, anthelmintic, cholagogue, demulcent, diuretic, expectorant, pectoral, purgative, tonic. It can be used either fresh or dried and is best harvested in October or November, though it can be collected until February. The leaves can also be used but are less active. A tea made from the roots is used in the treatment of pleurisy, hives, sore throats and stomach aches and as a mild laxative for children. It was also considered of value for lung ailments and liver diseases. The poulticed root is applied to inflammations. A tea or syrup of the whole plant is anthelmintic.
Alterative: Causes a gradual beneficial change in the body, usually through improved nutrition and elimination, without having any marked specific action.
Anthelmintic: Expels parasites from the gut.
Cholagogue: Increases the flow of bile and its discharge from the body.
Demulcent: Soothes, lubricates and softens irritated tissues, especially the mucous membranes.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Expectorant: Clears phlegm from the chest by inducing coughing.
Pectoral: Relieves respiratory diseases, a remedy for chest diseases.
Purgative: A drastic laxative causing a cleansing or watery evacuation of the bowels, usually with a griping pain.
Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.
Other
Rating: 3
Plants can be grown as a ground cover in a shady position. They form a spreading carpet and are best spaced about 30cm apart each way. The ash of burnt leaves is rich in carbonate of potash.
Insecticide: Kills insects.
Potash: Used for making glass, soap and as a fertilizer.
Food Forest: Plants for Edible Forest Gardens and Food Forests.
Ground cover: Ground Cover
How it is grown
Landscape Uses:Border, Container, Erosion control, Foundation, Ground cover, Massing, Rock garden, Woodland garden. Easily grown in most light soils. Prefers a soil of leaf mould and a cool but not too moist clay. Prefers a cool damp shady position. Thrives in dry shade. Established plants are drought tolerant. They grow well on drystone walls. Plants often grow as epiphytes. Members of this genus are rarely if ever troubled by browsing deer. A rather variable plant, it is considered to be an aggregate species of several very similar species. Only the roots should be planted, the rhizome being fixed to the surface of the soil. Special Features: Attractive foliage, Not North American native, There are no flowers or blooms. Polypodium virginianum (Polypodium vulgare subsp. virginianum (L.) Hultén is a synonym of Polypodium virginianum L.) commonly know as rock cap fern, or common polypody tolerates hardiness zones down to 3. It prefers acidic soil. It is a small evergreen species of fern native to the Eastern United States and Canada. It generally grows on rocks and occasionally on tree roots in nature. A small rhizomatous fern with narrow leaves 8–40 centimetres (3.1–15.7 in) long and 3–6 centimetres (1.2–2.4 in) wide. Polypodium virginianum typically grows on boulders, cliffs, and rocky slopes and does not need well-developed soil. The plant is heat tolerant in zones 9 through 1. (Plant Hardiness Zones show how well plants withstand cold winter temperatures. Plant Heat Zones show when plants would start suffering from the heat. The Plant Heat Zone map is based on the number of "heat days" experienced in a given area where the temperature climbs to over 86 degrees F (30°C). At this temperature, many plants begin to suffer physiological damage. Heat Zones range from 1 (no heat days) to 12 (210 or more heat days). For example Heat Zone. 11-1 indicates that the plant is heat tolerant in zones 11 through 1.) For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is a clumper with limited spread. The root pattern is rhizomatous with underground stems sending roots and shoots along their length.
Propagating it: Spores - best sown as soon as they are ripe, though they can also be sown in the spring. Sow them on the surface of a humus-rich sterilized soil. Keep the compost moist, preferably by putting a plastic bag over the pot. Pot on small clumps of plantlets as soon as they are large enough to handle and keep humid until they are well established. Do not plant outside until the ferns are at least 2 years old and then only in a very well sheltered position. Division. This is best done in the spring but it succeeds at most times of the year.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge; not Deep Shade; Ground Cover; North Wall. In. East Wall. In.
Habit: Fern
Hardiness: 3-6
Growth: Fast
Soil: Light (sandy), medium, heavy (clay)
Shade: Full shade, semi-shade
Moisture: Dry, moist
Things to keep in mind
Although we have found no reports of toxicity for this species, a number of ferns contain carcinogens so some caution is advisable. Many ferns also contain thiaminase, an enzyme that robs the body of its vitamin B complex. In small quantities this enzyme will do no harm to people eating an adequate diet that is rich in vitamin B, though large quantities can cause severe health problems. The enzyme is destroyed by heat or thorough drying, so cooking the plant will remove the thiaminase.