The Hart’s Tongue fern is not just any other typical fern. Its distinctive shape, looks, and growing behavior give it a unique place in the world of plants.
With a scientific name that sounds like a spell out of a Harry Potter movie, Asplenium scolopendrium has long tongue-like fronds and vibrant, refreshing color.
This plant is also known as Horse Tongue fern, Christ’s Hair fern, and Burn Weed fern. Read on to know all about how to care for this plant.
Hart’s Tongue Fern Care
Hart’s Tongue fern likes to grow in humus-rich, well-draining soil. It does not need more than 3 hours of bright indirect light a day. Water it every time the top few inches of soil dry out to maintain consistent soil moisture. The ideal temperature range and humidity are 50-65°F (10-18 °C) and 70%.
Soil
Hart’s Tongue fern likes to grow in humus-rich, well-draining soil. It can grow in sand, loam, heavy clay, and even chalk, with soil pH levels ranging from slightly acidic to highly alkaline. However, it thrives in light, sandy soils, and alkaline soils. They prefer calcareous content in the soil.
Your Hart’s Tongue fern will love loose soil that is high in organic content. Although they are a resilient species and can tolerate heavy clay soils, they will perform best when soil is light and loose.
While the plant will tolerate light to heavy soils, it cannot withstand waterlogged soil and suffer from root rot. Make sure the soil does not get waterlogged and does not get compacted.
When it comes to preferred soil pH levels, this fern stands out from the majority of ferns. Most ferns like to grow in slightly acidic soil, but this one here prefers alkaline soil.
Hart’s Tongue fern can tolerate highly alkaline to slightly acidic soil, but the optimum pH range is 7-8.5. It will love its home if the soil contains some calcium carbonate, chalk content.
The fact that it is naturally found growing in rock crevices, wall cracks, and as an epiphyte tells us that its roots need a lot of air to breathe and needs well-aerated soil.
Use a potting mixture that is high in organic content and contains different ingredients. This ensures that the soil drains well, is well-aerated, and also retains adequate moisture.
Light
Hart’s Tongue fern can grow in heavy to partial shade. It does not need more than 3 hours of bright indirect light per day. Excessive exposure to bright light can lead to the foliage turning yellow. It prefers a spot in front of a North or West facing window. Protect it from harsh sunlight.
Hart’s Tongue fern is a plant of the deep woods and naturally grows in heavy shade. It is also found in light woodlands with light shade. It grows on north-facing walls, and rock faces too.
The natural growing patterns indicate that this plant does not like direct sunlight at all. Exposure to direct harsh sun rays can burn the fern’s leaves.
Even excessive exposure to bright indirect light can dull the appearance of your fern and cause the foliage to turn yellow.
Keeping in mind the sparse light requirements of this plant, you are only recommended to plant it outdoors somewhere that has deep shade under dense tree canopies or with a north-facing wall.
This is not one of the porch or patio ferns as the open space gets too much bright light. You can easily grow it indoors close to north or west-facing windows.
Water
This fern naturally grows in places that are moist all year round. Hart’s Tongue fern likes consistent soil moisture and doesn’t like to be left thirsty at all. You should water it every time the top few inches of soil dry out. Reduce watering by almost half in the winter.
Hart’s Tongue fern is delicate when it comes to its water requirements and will quickly start wilting if left without water. You need to water it regularly and mulch the soil well.
Adequate soil moisture present at all times is a critical part of Hart’s Tongue fern care. Along with using water-retaining soil, water the plant punctually when the topsoil gets dry.
You need to be extra careful because this plant is also not tolerant of overwatering. Water should never be left standing in its pot for a long time.
Excess water should always flow out of the drainage hole.
You will have to significantly cut down water in the winter season because transpiration and evaporations rates fall considerably in this season.
Avoid watering the plant directly from the top. Water sitting on the foliage will lead to foliage rot.
The best practice to water these plants is to water in the mornings and directly to the base of the plant and the roots and not the foliage.
If your tap water contains chlorine, fluorides, or other hard elements, using tap water to water this fern is not recommended. You can alternatively use filtered or drinking water for your elegant fern.
If there is no other option, let tap water sit overnight. The majority of chlorine evaporates, and the water is safer for your plant.
Temperature
The Hart’s Tongue fern is native to Europe and some American states and prefers cool temperatures. The ideal temperature range for this fern is 50-65°F (10-18 °C). It cannot tolerate hot temperatures. It is hardy to USDA Hardiness zones 4-9. The growth rate slows down in the winter months.
Tolerance to low temperatures is another unique aspect of Hart’s Tongue fern care. There aren’t many ferns that can tolerate temperatures as low as this species.
This plant is native to Europe and found in some US states such as Tennessee, Alabama, Michigan, New York, and even Ontario in Canada.
Hart’s Tongue fern is nothing like the tropical fern and can withstand pretty low temperatures.
They are hardy to USDA zones 4-9, which means this plant can tolerate below-freezing temperatures. But it should be protected from frost.
If growing out in the open and unshaded by a tree canopy, it is recommended to bring the plant indoors on freezing winter nights.
Water this plant frequently when the temperatures rise in the summer. The Hart’s Tongue fern is not a suitable plant to grow if summer temperatures easily cross the 90°F (32°C) mark in your climate.
Humidity
High humidity is a much important factor these plants need to thrive as compared to temperature. The fern likes at least 70% humidity. Foliage turns dull and crispy brown at the edges if placed in low humidity. Use a humidifier, pebble tray, or place the plant in the bathroom for optimum humidity.
Usual indoor humidity levels are nearly not enough for Hart’s Tongue fern to thrive. The normal 5-10% indoor humidity levels will inevitably lead to a suffering plant if certain steps are not taken.
Using a humidifier or a pebble tray are the two most straightforward ways to make up for the required humidity levels for your plant.
Having a humidifier run nearby can increase the humidity levels by 50-60%, which is just what your Hart’s Tongue fern needs.
If you don’t have many indoor plants to care for, a pebble tray is also a viable option. Fill a tray with pebbles and place the plant pot over the pebbles.
Add water to the tray so that it fills up to 3/4th of the tray. The water will slowly evaporate from the tray, increasing the moisture content around the plant’s foliage.
Bathrooms are naturally perfect places for growing ferns. Moreover, your Hart’s Tongue fern will not need any heating. It can do well if left in the bathroom with adequate light and natural bathroom humidity.
Fertilizer
The frequency of fertilizing your Hart’s Tongue fern depends on the potting mix you’ve chosen to plant it. If the potting mix contains minimal or no organic content, you can fertilize the fern every month with a liquid fertilizer diluted to half strength. Always water your plant before fertilizing.
Ferns are not heavy feeders and will not need punctual fertilization. The need for fertilizer is even less when you’ve planted it in nutrient-rich, organic soil.
But if the soil is deficient in organic matter and the plant is growing in a small pot, liquid fertilizer can be used monthly.
Growth
Hart’s Tongue fern is an evergreen fern that can grow to 2 feet in height and width. It is a slow-growing plant belonging to the Aspleniaceae genus. The tongue-shaped fronds are shiny green and leathery in texture. The leaves have a unique manner of unrolling vertically, making it a sight to watch.
Another trait that sets this fern apart from other ferns is that its leaves are not pinnate. This means the leaves are not arranged on either side of the frond but are entirely closed.
This makes a frond look like a whole leaf. The leaves, or fronds, are erect and grow upright from the rhizome. They may arch over when they get tall enough.
The fern gets the name ‘Hart’s Tongue’ from the fact that its leaves look like the tongue of a male deer. Not to mention, a male deer is called a hart.
These plants can’t reproduce sexually. They have spores arranged on the underside of each frond that look like small millipedes.
Potting
Hart’s Tongue fern does not need a large pot to grow well and might grow better if it is slightly root-bound. They can be grown in any type of pot, but terra cotta pots are recommended to keep the rootball cool and aerated. It can also be grown in hanging baskets or fancy containers with drainage.
Regardless of the pot you choose to plant your Hart’s Tongue fern, you must always choose a pot that has drainage holes.
If a pot has very small drainage holes, line the bottom of the pot with small rocks or pebbles to prevent it from getting clogged and maintain adequate drainage.
Hart’s Tongue Fern Propagation
You can propagate this fern by spores and plant division in the spring. Sow the spores when ripe, and they will germinate in 1-3 months from when they’re sown in the spring. Young ferns can also be divided from the mother plant to grow in a separate pot.
Propagating Hart’s Tongue fern by spores is relatively easier than growing other kinds of ferns by the same method. This is because the spores of this plant are visible to the naked eye, and ripe spores can be differentiated from unripe ones.
Sow the ripe spores in a moist, humus-rich starting mix in spring. To keep the medium moist at all times, cover the container with a plastic bag.
When the germinated baby plants are big enough to support themselves, carefully pot each clump separately. Keep them in a protected environment until leaves are 15 cm long.
You can also divide new baby ferns from the mother plant by exploring the rootball and cutting off baby plants with their own root system.
Pot the young plants in a humus-rich and moist mix and keep them in a protected environment until they get established.
Common Problems with Hart’s Tongue Fern
This fern is not very susceptible to typical pests or diseases. Although some pests may invade the foliage, they can efficiently be dealt with by the usual remedies such as Neem oil spray or other mild insecticides.
The plant is, however, susceptible to root rot and crown rot. Both of which are caused by improper watering practices.
Avoid overwatering the plant and do not let water sit for too long on the foliage to prevent foliar fungal diseases.
Conclusion
The Hart’s Tongue fern is one of the most distinctive ferns you can grow at your home, and it is sure to catch every visitor’s eye due to its vibrant, refreshing colors.
Although a bit different than most ferns, caring for this elegant plant is easy as long as its humidity, water, and temperature requirements are kept to their liking.
Frequently Asked Questions about the Hart’s Tongue Fern
Is Hart’s Tongue fern toxic to pets?
Fortunately for joint plant and pet parents, Hart’s Tongue fern has no reported toxic effects on dogs or cats.
Does Hart’s Tongue fern flower?
Hart’s Tongue fern is a true fern and does not produce any flowers or fruit. It naturally reproduces asexually through the dispersal of spores.
Daniel has been a plant enthusiast for over 20 years. He owns hundreds of houseplants and prepares for the chili growing seasons yearly with great anticipation. His favorite plants are plant species in the Araceae family, such as Monstera, Philodendron, and Anthurium. He also loves gardening and is growing hot peppers, tomatoes, and many more vegetables.