DORADILLA: CHARACTERISTICS, HABITAT, CULTIVATION AND USES - BIOLOGY - 2025

The golden doradilla (Ceterach officinarum) or Asplenium ceterach L. is a small fern belonging to the Aspleniaceae family. It is characteristic of shady or illuminated rocky environments, being an easy species to distinguish due to its abundant lobular fronds of bright green color on the upper side and golden-brown on the underside.

Native to Europe and North Africa, it lives in rock fissures, walls and walls, generally on calcareous rocks. Indeed, it grows on limestone soils and shady environments with certain conditions of temperature and humidity.

Doradilla (Ceterach officinarum). Source: © Hans Hillewaert

Depending on the region or artisanal use, it has different names, being known as adoradilla, doradilla, dorada, doraílla, doradillo, golden capilera or dorailla herb. As well as ceterach, maidenhair, scolopendria, golden grass, silver grass, ormabelarra, stonebreaker, pulmonaria, pulipodio, sardineta, bravío tea, golden grass or morenilla stringer.

In low humidity conditions, the doradilla curls, exposing the scales or paleas on the underside of its fronds. These golden colored structures reflect light and have the function of protecting the sori from heat, hence their name "doradilla".

In dry season, when the sea bream curls up, it acquires a brittle and dry appearance, remaining in a dormant state for a long time. However, when the rains arrive, the plant hydrates, recovers its turgor and its green color will begin to shine.

At an ecological level, the Ceterach officinarum species is an excellent indicator of the water requirements of the ecosystem. Indeed, doradilla suffers from poikilohydria, that is, it lacks a mechanism to regulate water content and prevent desiccation.

On the other hand, this species contains a series of secondary metabolites such as tannins, phenolic acids, flavonoids, xanthones and soluble silicates. These compounds provide various medicinal properties, being traditionally used as a diuretic, to alleviate liver and kidney conditions, as well as tonic and pectoral.

General characteristics

Morphology

- Species: Ceterach officinarum Willd.

Synonymy

- Asplenium ceterach L.

- Ceterach officinarum subsp. officinarum Willd.

- Ceterach officinarum Willd.

- Ceterach vulgare var. crenatum Samp.

- Ceterach vulgare Druce.

Etymology

- Ceterach: the name of the genus comes from the Greek "satiray" which means doradilla.

- officinarum: the specific epithet comes from the Latin «office, -ae», which means «laboratory» and refers to its curative and therapeutic properties.

Detail of the underside of the doradilla leaves. Source: Bernd Haynold

Habitat and distribution

The doradilla is native to central-western Europe, including the Mediterranean basin, the Iberian Peninsula, the Balearic Islands and the Middle East. Its natural habitat is located between cracks in rocks, dry walls or cliffs, on limestone substrates with thin layers of earth.

Indeed, it grows along cracks or crevices of rocks and buckles, generally of limestone origin. It is located at altitude levels between 0 and 2700 meters above sea level, in cool and shady places, although it is a species resistant to insolation.

Ceterach officinarum is part of the class Asplenietea trichomanis or group of rock plants that live in rocky areas and receive direct rain. Most of these species are made up of camephytes, geophytes or hemicryptophytes, such as Asplenium trichomanes, Phagnalon saxatile and Sedum dasyphyllum.

The doradilla adapts to conditions of high temperature and strong incidence of solar radiation in very hot areas. Likewise, it requires dry soils, slightly acidic and poor in nitrogen, of calcareous origin with a high content of calcium carbonate.

Doradilla in its natural habitat. Source: Bernd Haynold

Culture

Although the doradilla is a species that grows in inhospitable environments, such as inaccessible rock crevices on slopes, it can be cultivated. In fact, its propagation can be carried out without problems in gardens and rocky areas only if the basic conditions of its natural habitat are maintained.

This species grows on soils with a sandy or sandy loam texture, with good drainage and constant humidity. In fact, the best results are obtained in soils with an alkaline pH of calcareous origin and a high content of mineral salts.

Commercially grown doradilla plants require intermediate watering that tries to maintain constant humidity in the substrate. Indeed, factors such as temperature, risks, environmental humidity, solar radiation, substrate texture and nutritional conditions must be taken care of.

A critical aspect is the frequency of irrigation, since although constant humidity must be maintained, it is necessary to avoid waterlogging. Doradilla is susceptible to waterlogged substrate and the plantation must have good drainage, otherwise the root system will be affected.

In relation to lighting requirements, it is not very demanding in terms of shading conditions. In fact, it can be installed in semi-shady conditions up to full sun exposure, both conditions do not negatively affect its proper development.

Relative humidity and temperature levels are important for this crop, with adequate ranges of 85-95% humidity and up to 12-15 ºC in winter. Indeed, environmental humidity is critical, since in dry environments the leaves tend to sag and take on a dry appearance.

The multiplication of this species is carried out by means of shoots or division of cuttings, just at the beginning of spring. The fertilization requirements are minimal, which can be supplied with an organic fertilizer or foliar fertilization.

Maintenance and sanitation pruning are convenient to avoid the incidence of pests or diseases. For growing in pots, maintenance pruning is recommended to slow growth and promote the development of more vigorous fronds.

Group of doradillas. Source: Pauline Eccles

Applications

Medicinal

Doradilla contains various active compounds, such as organic acids, tannins or mucilages that provide it with certain medicinal and therapeutic properties. In fact, astringent, diuretic and digestive properties are attributed to it ingested as an infusion of the leaves three times a day.

Traditionally, it is used as an antitussive, choleretic, diuretic, hypotensive, hypoviscosizing and general tonic. Likewise, it is recommended for those treatments that require increased urination or genitourinary conditions, such as cystitis, oliguria, urethritis or urolithiasis.

On the other hand, its intake contributes to the regulation of disorders related to arterial hypertension, hyperuricemia, hyperazotemia, gout, edema and fluid retention. It is also used in the prevention of arteriosclerosis, bronchitis, biliary dyskinesias, kidney problems, coughs, colds, flu and the common cold.

One of its main applications occurs during the treatment of childbirth, since it contributes to the lower intake of medications. Fresh or dried leaves are boiled in water for 5 minutes, taken a glass three times a day or used as a sitz bath.

An effective tonic for pectoral disorders or cough remedy is made by boiling 30 grams of leaves per liter of water. Heat for 20 minutes, let it rest and filter. Then it is drunk hot with drops of lemon and sweetened with honey.

This toner is also effective in strengthening the mood after periods of convalescence, improving the general conditions of the body and calming fatigue.

Doradilla in a dormant or dehydrated condition. Source: BerndH

Alcoholic beverage

In some regions of the Iberian Peninsula, such as Catalonia and the Balearic Islands, an alcoholic drink or "herbes" is made based on doradilla. The way of preparation consists of marinating the fresh doradilla leaves in brandy, with anise, pomace, green walnuts or fennel.

Cosmetology

Traditionally, the cooking of fresh doradilla mixed with ash was used in Aragon to wash and strengthen the hair. In the Balearic Islands, mainly in the Majorca region, this decoction is used to lighten the tone of the hair.

Recreational uses

In the traditional games of many Iberian regions, the boys and girls give the name of "sardineta" to the doradilla leaves, specifically to the fronds divided into small parts used when playing the "little kitchen".

Contraindications

There is no reference on the toxicity of any of the phytochemical components of doradilla, nor are there reports on side effects or contraindications. However, its administration is not recommended to pregnant women, lactating women, young children or patients with chronic diseases.

References

1. Carrió, E., Garnatje, T., Parada, M., Rigat M. and Vallès, J. (2014) Ceterach officinarum Willd. Spanish Inventory of Traditional Knowledge related to Biodiversity.
2. Ceterach officinarum. (2019). Wikipedia, The Free Encyclopedia. Recovered at: es.wikipedia.org
3. Doradilla (Ceterach officinarum) (2019) Atlantic Botanical Garden. Recovered at: botanico.gijon.es
4. Rivas-Martínez, S. and Coauthors. (2011) Asplenietea trichomanis. Map of series, geoseries and geopermaseries of vegetation in Spain. Memory of the potential vegetation map of Spain.
5. Wikipedia contributors. (2019). Asplenium ceterach. In Wikipedia, The Free Encyclopedia. Recovered at: en.wikipedia.org
6. Živković, S., Skorić, M., Šiler, B., Dmitrović, S., Filipović, B., Nikolić, T., & Mišić, D. (2017). Phytochemical characterization and antioxidant potential of rustyback fern (Asplenium ceterach L.). Lekovite sirovine, 37, 15-20.