Quick Answer
Bird’s nest ferns can survive and even thrive when their roots are kept constantly wet, as long as their fronds remain relatively dry. This makes them well-suited for terrariums and vivariums where the lower portion of the plant sits in water, while the upper fronds remain above the water line. However, bird’s nest ferns are tropical plants that prefer high humidity rather than soggy soil. Letting the fern sit directly in water for extended periods can lead to root rot.
Bird Nest Fern Overview
The bird’s nest fern, also known as nest fern or asplenium nidus, is a tropical fern native to southeast Asia, eastern Australia, Hawaii, and eastern Africa. It is an epiphytic plant, meaning it grows on other plants and objects like the branches and trunks of trees rather than rooting directly in soil. In the wild, bird’s nest ferns grow in the humid, shady understory of tropical rainforests.
Some key facts about bird’s nest ferns:
– Genus and species: Asplenium nidus
– Native habitat: Tropical rainforests
– Mature size: 1-3 feet tall and wide
– Light requirements: Bright, indirect light
– Watering needs: High humidity, moderately moist soil
– Temperature range: 60-80°F
The bird’s nest fern gets its name from its rosette growth pattern, with overlapping fronds that form a nest-like structure. The fronds are long, narrow, and have an undulated or ruffled appearance. They emerge from the center of the plant on short stems called stipes. Mature plants may produce tiny plantlets along the edges of their fronds that can drop off and root to form new plants.
Bird Nest Fern as an Aquatic Plant
The bird’s nest fern has a reputation for being able to grow as an aquatic or semi-aquatic plant. This refers to keeping the roots permanently wet while the fronds stay relatively dry. Some popular ways to grow bird’s nest ferns “in water” include:
- Planted in pots set inside aquariums or paludariums so the base sits underwater.
- Mounted on driftwood or rocks above a pond or fountain.
- Placed in glass terrariums or Wardian cases designed to create a humid environment.
When grown as an aquatic plant, the bird’s nest fern’s roots can handle being submerged indefinitely. They have specialized cells called velamen that absorb moisture and nutrients. This adaptation allows epiphytic ferns to flourish in the humid, tropical environments they evolved in. As long as the fronds themselves stay relatively dry, the plant thrives in wet feet and high humidity.
Growing bird’s nest ferns as aquatic or semi-aquatic plants takes some trial and error. The biggest challenges are preventing the fronds from staying too wet and maintaining good air circulation around the plant. Stagnant conditions can lead to fungal problems.
Caring for Bird Nest Ferns in Wet Environments
If you want to grow bird’s nest ferns as aquatic or semi-aquatic plants, here are some tips:
Provide bright, indirect light
While they prefer shade, bird’s nest ferns need good light to thrive. Place them in bright locations filtered by sheer curtains or shaded by other plants. Make sure fronds don’t get direct sun, which can scorch them.
Use nutrient-rich water
Because they are only absorbing nutrients through their roots and not soil, add diluted fertilizer to the water 1-2 times per month during the growing season. Use one specifically formulated for ferns.
Ensure good air circulation
Stagnant, soggy air will cause foliar problems. Use fans to keep air moving. Open terrariums/Wardian cases to allow air exchange. Change water frequently.
Keep fronds dry
Avoid misting bird’s nest ferns directly. Allow fronds to fully dry out between waterings. Absorbent wicking material can help remove excess moisture.
Provide high humidity
Use open containers of water, pebble trays, and humidity domes to keep humidity around 70-80%, which bird’s nest ferns prefer. Lower humidity causes frond tips to turn brown.
Watch for pests
Wet conditions can lead to fungal issues and pest problems. Watch for signs of disease, spider mites, scale, and mealybugs. Treat promptly to avoid spreading.
Don’t let roots sit in stagnant water
Stagnant water can lead to root rot. Make sure water is flowing and aerated. Change out water frequently to prevent it from becoming stagnant.
Repot annually
Repotting into fresh media annually will help refresh nutrient levels. When roots are constantly wet, they are unable to get nutrients from breaking down organic matter.
Troubleshooting Bird Nest Ferns in Aquatic Environments
If your bird’s nest fern is struggling when grown as an aquatic plant, here are some common issues and solutions:
Problem | Cause | Solution |
---|---|---|
Slimy roots | Excess moisture | Repot in fresh media, allow roots to dry out between waterings |
Yellowing fronds | Overwatering | Allow fronds to dry before watering again |
Brown leaf tips | Low humidity | Increase humidity around plant |
Poor growth | Insufficient light | Place in brighter location |
Leaf spots | Fungal disease | Improve air circulation, treat with fungicide |
The most common problems arise from the roots staying too wet while the fronds don’t get enough air circulation. Adjusting watering practices, increasing air flow, and providing adequate lighting should get a struggling bird’s nest fern back on track.
Alternative Aquatic Plants
While bird’s nest ferns do well as semi-aquatic plants, some other options to consider fully submerging in water features include:
Anubias
This aquatic flowering plant has broad, dark green leaves. It grows slowly and thrives with its roots fully submerged and rhizome above water. The hardy plant does well in low light.
Java Fern
A versatile aquatic fern that can grow fully submerged or with leaves above water. Likes being attached to rocks or driftwood. Requires low light with no CO2 supplementation needed.
Bacopa
Also known as moneywort, this creeping aquatic plant grows rapidly. It spreads across the bottom with small leaves reaching up toward light. Tolerates a wide range of conditions.
Cryptocorynes
Commonly called crypts, many species of this aquatic plant grow well fully submerged. They have green, reddish or bronze leaves and adapt to low light conditions.
Hornwort
A freshwater aquatic plant with long, thin, forked leaves. It grows rapidly, propagating itself through cuttings that root. Great for the background of aquariums.
These fully aquatic plants can provide alternatives to trying to grow more moisture-loving terrestrials like bird’s nest ferns underwater.
Conclusion
While bird’s nest ferns thrive in humid conditions, they are not truly aquatic plants. Their roots can handle constantly wet conditions, but their fronds need air circulation and should dry out between waterings. Growing bird’s nest ferns “in water” takes careful attention to prevent disease and other problems. Their moisture-loving nature makes them ideal for terrariums and Wardian cases rather than fully aquatic displays. For permanently underwater applications, fully aquatic plants make better choices. However, bird’s nest ferns can make dramatic centerpiece plants in the right semi-aquatic setting with some specialized care.