Bird's nest ferns (Asplenium nidus) are actually one of two Asplenium species found in cultivation. The other, often called the spleenwort or mother fern (Asplenium bulbiferum), is much harder to grow and looks nothing like its cousin. These ferns are naturally epiphytic, and in their rainforest homes, they can be found growing high in the crooks of trees. They grow in a series of erect, spoon-shaped, and apple-colored fronds that rise from a central rosette.
Healthy plants can have fronds up to three feet, but this is rare in most indoor situations. These are beautiful plants but require a bit of babying to reach their fullest potential.
If you follow the correct growing conditions for your bird's nest fern, it will likely live for many years and always look its best.
- Light: Filtered light to light shade. Don't expose to direct sun other than very early morning sun.
- Water: These are true jungle plants—keep their compost moist and provide the highest humidity possible.
- Temperature: Bird's nest ferns will begin to suffer below about 55 F for prolonged periods. They are best kept between 70 F and 80 F, with high humidity. A warming pad will often help dormant plants.
- Soil: Loose, rich organic compost.
- Fertilizer: During growing season, fertilizer weekly or biweekly with weak liquid fertilizer. Don't put fertilizer pellets in the central cup.
Bird's nest ferns are not easy to propagate and cannot be divided, as other fern species can be. They are usually raised from spore or tissue culture, which means propagation is usually beyond the reach of most home growers.
Bird's nest ferns prefer to be slightly underpotted. As naturally epiphytic plants, they are used to growing in a minimum of organic material, and mature plants will elongate above the soil level as the fern grows and sheds lower leaves.
The problem, of course, is that large ferns will easily tip over their smaller pots. When repotting, usually every other year, use the next pot size up and refresh the compost.
Some varietals of bird's nest fern have been developed, usually with crinkled or frilly leaf margins. Mother fern (also called spleenwort) is sometimes available at the nursery or online, but this is a much more difficult fern to grow indoors than bird's nest fern.
Bird's nest ferns are beautiful, and many conservatories and greenhouses boast impressively large specimens. They are a natural to group with orchids, bromeliads, and other rainforest plants in a display. The key to a healthy bird's nest fern is providing enough warmth and moisture. Given these two conditions, the ferns can withstand higher light levels. One of the best places to put a bird's nest fern is on a shower ledge or the wide edges of a luxury bathtub in a bathroom near a window, where it will get optimal humidity and warmth, along with sufficient light.