Black Spleenwort
Asplenium adiantum-nigrum
Family: Polypodiaceae
What it is like
Asplenium adiantum-nigrum is an evergreen Fern growing to 0.5 m (1ft 8in). See above for USDA hardiness. It is hardy to UK zone 6. It is in leaf all year, and the seeds ripen from June to October. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. 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 moist soil.
Height (m): 0.5
Where it is found
Rocky woods, hedgebanks, shady walls and rocks.
Most of Europe south of the Faroes, including Britain, to the Himalayas, N. and S. Africa.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 0
Medicine
Rating: 2
The plant is bitter, diuretic, laxative and ophthalmic. It is taken internally to treat diseases of the spleen, jaundice and ophthalmia. It is said to produce sterility in women. A decoction or syrup made from the fronds is emmenagogue, expectorant and pectoral. It is used to relieve troublesome coughs.
Bitter: Increases the appetite and stimulates digestion by acting on the mucous membranes of the mouth. Also increases the flow of bile, stimulates repair of the gut wall lining and regulates the secretion of insulin and glucogen.
Contraceptive: Prevents fertilization occurring in females.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Emmenagogue: Promotes or increases the menstrual flow. In early stages of pregnancy it can induce an abortion.
Expectorant: Clears phlegm from the chest by inducing coughing.
Laxative: Stimulates bowel movements in a fairly gentle manner.
Ophthalmic: Treats eye complaints.
Pectoral: Relieves respiratory diseases, a remedy for chest diseases.
Other
Rating: 2
A decoction of the herb is a good hair wash.
Hair: Plants used as hair shampoos, tonics, to treat balding etc.
How it is grown
Requires a partly shaded site with preferably less than 3 hours sunshine daily. Plants can be grown in old brick walls. Members of this genus are rarely if ever troubled by browsing deer.
Propagating it: Spores - best sown as soon as they are ripe on the surface of a humus-rich sterilized soil. Keep the compost moist, preferably by putting a plastic bag over the pot. Germinates in spring. Spring sown spores germinate in 1 - 3 months at 15°c. Pot on small clumps of plantlets as soon as they are large enough to handle and grow them on in light shade in a cold frame or greenhouse. Keep them humid until they are well established. When they are at least 15cm tall, plant them out into their permanent positions in late spring or early summer.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge; not Deep Shade; Hedgerow; North Wall. In.
Habit: Fern
Hardiness: 5-9
Growth:
Soil: Light (sandy), medium
Shade: Full shade, semi-shade
Moisture: 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.