Herb: Royal Fern

Latin name: Osmunda regalis

Family: Osmundaceae

Medicinal use of Royal Fern:

The root is astringent, diuretic, tonic and vulnerary. It is useful in the treatment of jaundice and removing obstructions of the viscera. The fronds are used to make compresses for external application to wounds and rheumatic joints - for which purposes they are fairly effective. An infusion of the fronds, combined with wild ginger roots (Asarum species) has been used in the treatment of children with convulsions caused by intestinal worms.

Description of the plant:


2 m
(6 1/2 foot)

Habitat of the herb:

Swampy areas, fens and damp woodland.

Other uses of Royal Fern:

The hairs of the plant are mixed with wool and are used in making cloth. The roots are the source of "Osmunda fibre", this was once widely used for potting orchids and other epiphytes. Plants can be grown as a ground cover when spaced about 1 metre apart each way.

Propagation of the herb:

Spores - they very quickly lose their viability (within 3 days) and are best sown as soon as they are ripe on the surface of a humus-rich sterilized soil in a lightly shaded place in a greenhouse. Keep the compost moist, preferably by putting a plastic bag over the pot. Plants develop very rapidly, 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. Cultivars usually come true to type. Division of the rootstock in the dormant season. This is a very strenuous exercise due to the mass of wiry roots.

Cultivation of Royal Fern:

Swampy areas, fens and damp woodland.

Known hazards of Osmunda regalis:

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.

Plant information taken from the Plants For A Future.