OSMUNDA REGALIS: CHARACTERISTICS, HABITAT, CULTIVATION, DISEASES - BIOLOGY - 2025

Osmunda regalis or royal fern, is a species belonging to the Polypodiopsida family. It is considered by many to be the most beautiful of all ferns and develops plumes similar to wilted flowers. Besides royal fern, it is also commonly known as flowered fern, royal osmonde, or male fern.

It is a kind of majestic fern. It has a thick, horizontally extended woody rhizome, which is covered by the remains of the petioles. The leaves are formed by pinnae arranged oppositely on each side of the canaliculate rachis, the pinnae are ovate-lanceolate, while the pinnules are oblong-lanceolate and their edges can be whole or serrated.

Royal fern or flowered fern. Source: Alex Lomas

It reproduces through spores located in the sporangia, which are not concentrated in sori, but are dispersed on the underside of fertile leaves. These sporangia are subglobose in shape and arranged in the shape of a panicle.

Regarding its uses, it is widely used to make pads or bases to grow orchids. It has medicinal properties, within which the rhizome is mainly used for purposes such as wound treatment, deworming, astringent or diuretic, among others.

characteristics

Appearance

It has an underground rhizome-like stem. During the summer it behaves as a deciduous species whose behavior is to orient its spore-producing fronds (leaves) towards the top, thus making it seem that the fern is flowering.

The fertile fronds give a flowery appearance to the royal fern. Source: wikimedia commons.

In the fall time, the leaves turn from green to golden-bronze and then die. During the spring, the leaves turn green again.

This species can reach 60 cm in its juvenile age, but reaches up to 160 cm in adulthood or maturity. The diameter of the royal fern can be up to 40 cm.

Leaves

The royal fern has two types of foliage (fertile and sterile). The fertile leaves are shorter and more crowded, while the sterile leaves are long and grow messily.

The leaves or fronds are formed by pinnae (compound leaves), which are arranged on both sides of the rachis by parallel structures (bipinnate).

Reproduction

Like all ferns, reproduction takes place through spores that develop into sporangia that are arranged on the back of the pinnae.

During May or June, sporangia are formed from the meiotic process, which gives rise to more than 500 spores in each of these structures.

These spores are released during the month of July and are spread through the air, although some die, others germinate after finding the right conditions to develop.

Taxonomy

The name Osmunda is the name that the Saxons gave to the god Thor; while, the Latin name regalis means royal.

-Kingdom: Plantae

-Filo: Tracheophyta

-Class: Polypodiopsida

-Order: Osmundales

-Family: Osmundaceae

-Gender: Osmunda

-Species: Osmunda regalis L.

The royal fern has some synonyms such as: Aphyllocalpa regalis, Osmunda brayeri, Osmunda leschenaultii, Osmunda longifolia, Osmunda plumieri, Osmunda regalis var. longifolia, osmunda spicata, Struthiopteris regalis.

Illustration of Osmunda regalis. Source: Carl Axel Magnus Lindman

Habitat and distribution

Distribution

The royal fern thrives under optimal conditions in Europe, especially around the Mediterranean, in Africa, Asia and New Zealand. The spectabilis variety can be found in America, although it can also inhabit Italy, Ireland, Norway, Spain, the United States, Germany, Greece, Cameroon, Georgia, South Africa, India, Kenya and the United Kingdom.

Notably, this species can behave as a cosmopolitan. In fact, it is associated with complex vegetations, which can give reference to the evolutionary resistance of this fern.

Habitat

This species of fern can grow in peat bogs, humid forests, riparian forests, humid caves, rocks, swamp forests, but it necessarily requires a moist soil and a shady and cool environment. However, it can grow under the influence of the sun but in semi-shady conditions.

State of conservation

Although the International Union for Conservation of Nature considers the royal fern to be a species of least concern, it is also true that the abundance of this species is lower than in other years.

This indicates that the fern's habitat is being affected by factors such as agriculture, grazing, and anthropic effects, especially to build urbanizations and the like. For this reason, in some countries such as Bulgaria, Hungary, Iran, Luxembourg and Croatia it is considered a threatened species, as well as in Switzerland and Germany it is a vulnerable species.

Applications

Culinary

The royal fern is not exactly recognized for its use in cooking. However, in the Korean royal court, it represents a typical dish called namul, in which the young shoots (circines) are used as part of the vegetables.

Circines are used in some parts of the world as vegetables in gastronomy. Source: wikimedia commons.

Medicinal

Regarding its medicinal uses, both the roots or rhizomes and the fronds are used to treat rheumatic pain, jaundice, rickets and some skin wounds. The roots can function as astringent and also have diuretic properties.

For its part, the fronds combined with ginger are usually prepared as an infusion to treat intestinal parasites.

Ornamental

Another use, perhaps the best known, is to use its roots to make the fiber that supports other species such as orchids. At this point it is interesting to know that during the Soviet times tons of roots were exported to European countries (especially Russia) for growing these epiphytes and for horticulture in general.

In addition, this plant is used as an ornamental as part of gardens, functioning mainly as a hanging type specimen that, due to its rich and dense foliage, gives an exuberant appearance to the garden.

Pesticide

Also, the royal fern is used as a repellent for insects such as mealybugs, aphids, as well as to combat slugs. It is also sometimes used to preserve fruits due to the same pest repellent effect.

Ways of preparation

Depending on the medicinal use that you want to give to the royal fern, it can be prepared in the following ways:

Restorative

For this effect, 40 grams of the fern rhizome should be placed for each liter of water and boiled for 15 minutes. Once it is cold, this preparation can be sweetened with honey and 2 or 3 cups are taken every day. In the Nordic countries, this preparation can replace coffee or tea.

Dressing

The rhizome of the fern is the part that is most used for beneficial effects on health. In this case, cuts of about 50 grams are selected and boiled in a liter of water. Subsequently, the rhizome is squeezed and placed directly on the affected area until it heals.

Treatment of hernias

To do this, about 8 to 10 grams of the rhizome should be chewed twice a day for a week.

Another way to prepare it is by pulverizing the leaves or crushing them in a mortar. Then, the generated paste is added either to a hot drink, for example coffee, twice a day also for a week.

Antiseptic

To eliminate any infection or problems with any microorganism, 200 grams of a mixture of the foliage with the rhizome should be taken as close to the ground as possible, to increase its sterility. They can then be passed through a mortar and boiled in two liters of water for thirty minutes.

This preparation can be applied to areas affected by the infection, or it can even be used as a preventive bath in the event that the person is constantly exposed to biological risks.

Osmunda regalis. Source: I. Saček, senior

Culture

Light

Although the royal fern can grow in direct sunlight, it requires a perennial shaded space. To obtain this constant shadow effect, it is often grown in association with other larger species.

It is considered that, the greater the shade that this fern receives and its fronds are less dense, it can expand more than 3 m.

Temperature

The ideal temperature is higher than 28 ° C, that is, a warm climate. However, this fern can grow safely from 18 ° C to 35 ° C, as long as the other environmental requirements are met.

Regarding low temperatures, the royal fern is a species resistant to cold down to -25 ° C.

Floor

The royal fern requires moist, acidic soil with a constant supply of water. For its cultivation, it is necessary to place the spores in the soil for a maximum of three days since they normally do not survive for much longer.

The pH should be in the 3.5 to 5.5 range, and the soil should be poor in its nitrogen content.

With regard to the cleaning of the substrate, it is necessary that the dried fronds are removed at the beginning of each season.

Irrigation

The royal fern is a species that requires permanent humidity, therefore, watering must be abundant and frequent.

Sowing

The best time to plant this species of fern is in summer. To do this, the mature spores must be placed in a mixture of heather and a compost made from bark at a temperature of 15 to 18 ° C.

In gardens, it is often best associated with perennials but not other ferns. In this way, the royal fern can stand out and look better than combined with other genera or other relatives.

Diseases

This species of fern is resistant to diseases and pests. At least, the data available in the literature in this regard are very few. On the contrary, as already mentioned, this species works as a pest repellent.

References

1. BioEncyclopedia. 2015. Royal fern. Taken from: bioenciclopedia.com
2. Catalog of Life: 2019 Annual Checklist. Species details: Osmunda regalis L. Taken from: catalogueoflife.org
3. Ornamental plants 2019. Royal fern (Osmunda regalis). Taken from: Plantasornamentales.org
4. Iberian Flora. 2019. Osmunda L. Taken from: floraiberica.es
5. ESDEM Garden. 2019. Royal Osmonde, royal fern, flowering fern. Taken from: es.esdemgarden.com
6. BiomarMT. 2019. Royal Osmonde (Osmunda regalis). Taken from: biomarmicrobialtechnologies.com