Black maidenhair (Asplenium adiantum-nigrum)

The Asplenium adiantum-nigrum is a fern that does not grow much, in fact, it does not reach half a meter in height; however, it has fronds or leaves that make it look very pretty. In addition, due to its characteristics, it is extremely interesting to include it in plant compositions in shady or semi-shady corners of gardens.

As if that were not enough, it grows very well among the rocks. In fact, it is often found precisely there: on ancient walls and walls where moss grows. However, it can also be grown in pots.

Origin and characteristics of Asplenium adiantum-nigrum

Image – Wikimedia/ Gmich2012

The black maidenhair, as it is popularly known, is a fern that belongs to the genus Asplenium, native to the mountains of Europe, although it also lives in the United States, at altitudes greater than 1500 meters above sea level. It grows to 10 to 30 centimeters in height, starting from a short-length rhizome from which bi- or tri-pinnate fronds (leaves) sprout. These are 3 to 15 centimeters long by 2.5 to 7.5 centimeters wide.

Sori, that is, clusters of sporangia (where spores are produced), are found on the underside of fertile leaves, and appear between spring and autumn (from April to October in the northern hemisphere).

What are the care it requires?

If you want to have a fern of the Asplenium adiantum-nigrum species, you must bear in mind that it is a plant that, although not difficult, can become so if the climate does not favor its growth. And we must not forget that it grows in the mountains of temperate regions, so temperatures must be mild in summer and low in winter; otherwise, you would see that it has a slow development.

For the rest, you should know the following:


It is a plant that you have to grow outdoors, in an illuminated area where the sun’s rays do not reach it directly. As it does not grow much, it is highly recommended to plant many specimens together so that they form “piles” in the garden, or even in planters. In this way, it will undoubtedly stand out much more.


  • Garden: grows on old walls and walls with moss, but also on stony soils that are rich in organic matter.
  • Pot: Mix mulch with 50% perlite or quartz sand. To make the drainage even better, you can add a layer of about 2 centimeters of clay.


It must be irrigated immediately with rainwater or, failing that, one with a weak mineralization. It is important that the earth never dries up completely, since it is a fern that does not resist drought. But yes, it should not be planted in a pot without holes or in poorly drained soils, since otherwise its roots would die suffocated.

Also, when watering, avoid wetting the plant. The water has to go directly to the land, especially if at that moment the sun is still very high on the horizon. In fact, it is preferable to water in the late afternoon, since in this way the soil will remain humid for longer and the Asplenium adiantum-nigrum will be able to absorb the water for longer.


Image – Wikimedia/ Forest & Kim Starr

The black maidenhair is growing from spring to summer, and even continues to grow in the fall if it is mild. Therefore, in addition to watering it, it must be fertilized regularly with organic fertilizers. One of rapid efficacy and very rich in nutrients is guano, which is nothing more than the waste left by seabirds and bats after digestion. But be careful, it is very concentrated, and although it is natural, it must be used as it will be indicated on the package.

Other interesting fertilizers are chicken manure (if it is fresh, let it dry in the sun for ten days before using it), cow manure or mulch. Scoop a handful around the plant once every 15 to 30 days (depending on how long it takes to decompose).


It can multiply by spores in spring, or asexually by dividing the rhizome in late winter.


The spores have to be sown in low-rise seedbeds with mulch, so that they remain on the surface, somewhat buried. Then, it has to be watered and placed in semi-shade.

If they go well, they will germinate in about two weeks.

Rhizome division

To divide the rhizome you have to first extract the plant from the pot or the ground and with a disinfected hand saw divide the fern. Then, seal the wound with healing paste and plant it in another pot or in other areas of the garden. Finally, you have to water by adding rooting hormones or homemade rooting agents to the water.


Image – Wikimedia/ BerndH

The black maidenhair withstands temperatures down to minus 18 degrees Celsius ; however, the maximums should not exceed 30ºC.

Did you know this fern?

Related posts

Deja una respuesta

Tu dirección de correo electrónico no será publicada. Los campos obligatorios están marcados con *

Botón volver arriba