Christmas Fern
Polystichum acrostichoides
Family: Dryopteridaceae
What it is like
Form: Irregular or sprawling, Upright or erect.
Polystichum acrostichoides is an evergreen Fern growing to 0.6 m (2ft) by 0.5 m (1ft 8in) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 4. It is in leaf all year. Suitable for: light (sandy) and medium (loamy) 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 moist soil.
Height (m): 0.6
Where it is found
Wet woods and rocky slopes. Forest floor and shady, rocky slopes from sea level to 1500 metres.
Eastern N. America - Nova Scotia to Wisconsin, south to Florida, Texas and Mexico.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 1
Young fronds. No more details are given, but they are probably harvested as they unfurl and eaten cooked.
Medicine
Rating: 2
Christmas fern was employed medicinally by several native North American Indian tribes, who used it to treat a variety of complaints. It is little, if at all, used in modern herbalism. A tea made from the root is blood purifier, emetic and febrifuge. It is used in the treatment of chills, fevers, pneumonia, stomach or bowel complaints and rheumatism. A poultice of the root is used in the treatment of rheumatism. A decoction of the root has been massaged into rheumatic joints. The powdered root has been inhaled and then coughed up in order to restore the voice.
Antiaphonic: Restores the voice.
Emetic: Induces vomiting.
Poultice: A moist, usually warm or hot, mass of plant material applied to the skin in the treatment of burns etc.
Other
Rating:
Food Forest: Plants for Edible Forest Gardens and Food Forests.
How it is grown
Landscape Uses:Border, Container, Erosion control, Foundation, Ground cover, Massing, Rock garden, Woodland garden. Prefers a sandy humus-rich soil in a shady position that is moist even in winter. Tolerates part sun for up to 6 hours a day if the soil remains moist. Prefers a pH in the range 6.5 to 7.5. A very ornamental plant, it is hardy in all parts of Britain but is best grown in a greenhouse. Members of this genus are rarely if ever troubled by browsing deer. Remove old fronds from the plant in the spring because they may harbour fungal diseases. Special Features:Attractive foliage, North American native, Attracts butterflies, There are no flowers or blooms. The plant is heat tolerant in zones 8 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. An evergreen. 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.
Best place to grow: Woodland Garden Dappled Shade; Shady Edge; not Deep Shade;
Habit: Fern
Hardiness: 4-9
Growth: Medium
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.