The Temperate Database is in the process of being updated, with new records being added and old ones being checked and brought up to date where necessary. This record has not yet been checked and updated.
Common Name: Christmas Fern
Polystichum acrostichoides is a Evergreen Fern up to 0.60 metres tall.
It is harvested from the wild for local use as a food and medicine
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[
Eastern N. America - Nova Scotia to Wisconsin, south to Florida, Texas and Mexico.
Wet woods and rocky slopes[
]. Forest floor and shady, rocky slopes from sea level to 1500 metres[
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[
]. No more details are given, but they are probably harvested as they unfurl and eaten cooked.
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[
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[