Low humidity and underwatering are the two most frequent causes of browning fern leaves. Indoor humidity is normally around 10%, which causes the leaves to lose water and turn brown and crispy at the tips. Ferns prefer a humidity of 40%.
Most frequent causes of ferns becoming brown include:
|Causes:||The cause of browning fern leaves is:|
|minimal humidity||All indoor ferns are tropical or subtropical plants, and they need a humidity level of at least 30%, ideally 40%. Fern leaves indoors become brown and crunchy due to low humidity.|
|Underwatering.||Water ferns thoroughly, and keep the soil continually moist (but not saturated). Browning leaves are a result of dry soil.|
|tiny pots||Smaller pots may dry out too fast after watering, which could lead to the roots becoming pot-bound and causing the leaves to turn brown.|
|A lot of sun.||Ferns are accustomed to dwelling in the partial or complete shadow of the woodland and forest canopy. Too much might discolor the delicate foliage.|
|elevated temperatures.||Ferns like relatively cool temperatures of 10 degrees lower at night and between 65 and 75 degrees Fahrenheit during the day. The soil and foliage dry out and turn brown due to high heat.|
|Ferns outside turning brown in the fall.||Outdoor ferns lose their green leaves in the Spring and become brown in the Fall, giving the impression that they are dying.|
To save your fern with brown, decaying, crispy, dried-up leaves, keep reading to find out why it is going brown and how to apply the remedies.
Table of Contents
1. Low Humidity (Increase the Humidity to 40%)
Low humidity is typically the cause of indoor fern leaves turning brown. Tropical natives, indoor ferns can survive in environments with a humidity of 40% or more. The typical indoor humidity is 10%, which is too low and causes the fern’s leaves to become crispy, dried out, and brown.
The five most popular species of houseplant ferns, which are native to tropical locations with humidity levels typically ranging from 40% to 70%, are Boston, Maidenhair, Asparagus, Staghorn, and Java ferns.
Brown leaves are typically caused by this disparity in humidity because the low humidity dries out the ferns’ leaves, making them brown and crispy, which is the opposite of what they desire.
Numerous elements, including the following, can make indoor low humidity conditions worse and cause ferns to turn brown:
- the climate control. In addition to producing an unfavorable air current, air conditioning also dries the air and stains the tips of ferns’ leaf blades brown.
- compelled air Forced air produces a current of dry air that, like air conditioning, reduces humidity, raises temperature (which also dries out the soil more quickly and ferns like a temperature range of 65°F to 75°F), and makes leaves turn brown and crispy.
- heat sources. Forced air, central heating, or a fireplace are all examples of heat sources that induce convection currents in the home, which circulate dry air and dry up your fern plant.
The typical humidity in your home is still probably too low for your fern plant to endure even if these things don’t reduce humidity.
How to Fix It
Put your houseplants closer together to create a humid microclimate, or put your fern in a room with higher humidity, like the bathroom, and use a humidifier to provide the precise amount of humidity needed to stop your fern from going brown, in order to save a fern with brown leaves.
In order to successfully save a dying indoor fern, I always advise humidifiers since they can produce the ideal humidity for your fern that closely resembles its natural habitat. You can precisely control the humidity level and direct the mist around your fern with some humidifiers.
Place your fern so that its pot is sitting on the pebbles, above the water line, in a saucer of water filled with pebbles. To combat the dry air, the evaporation from the saucer makes the surroundings more humid throughout the day.
Although I must stress the significance of maintaining the pot above the waterline to enable for free drainage of excess water, ferns require constantly moist soil that is not soggy since this can lead to root rot.
Daily sprinkling with a spray bottle can also be beneficial, but too much misting can cause foliar disease, therefore I advise placing your fern next to other plants, putting it on a saucer filled with water, and using a humidifier.
Once you’ve made your fern’s habitat more humid, the increased humidity should stop more leaves from becoming brown.
To restore healthy development, remove any dry, brown, crispy leaf blades and leaflets using a pair of sharp pruners or scissors because the brown growth does not recover. As long as the humidity is continually at least 30% (preferably 40% for most species), pruning your fern does stimulate new, healthy green growth, and the fern should retain a healthy green.
The most crucial element for the health of your fern is a higher relative humidity level.
(For additional information, see my article on how to save a dying fern.)
2. Underwatering (Soil Should be Consistently Moist)
Underwatering is frequently the cause of fern leaves turning dark at the tips. Ferns prefer constant, even moisture in the soil around their roots. The leaves get brown, crunchy, and dried out due to a lack of moisture if the soil dries out in between watering sessions.
Ferns are all woods or forest plants that thrive in rich, organic soil that is typically made up of leaf mold.
Ferns have evolved to thrive in soil that holds a lot of moisture but is porous enough for extra moisture to drain away from the roots (preventing roots rot).
Brown leaf tips are one of the first indicators of stress if you water too infrequently or too little and the soil dries up. However, the fern’s browning from the base of the plant is another sign of dry stress.
How to Fix It
As often as necessary, water ferns to keep the soil regularly and evenly moist. The type of fern you have, its species, and its size will all affect how frequently you need to water it (the larger ferns have more leaves and more surface area from which to lose water).
If the fern is outdoors, you can test the soil to a finger’s depth to gauge the amount of moisture and gauge when your fern needs watering. Alternatively, you can feel the weight of the fern’s pot by lifting it; it should feel heavy after watering, then gradually lighter as the fern’s roots uptake the moisture in the following days.
Always give your fern a thorough bath as opposed to a gentle misting.
Water well, making sure that any extra water runs down through the drainage holes in the pot’s base.
This makes sure that the soil is continually and uniformly moist around the roots of the fern so that those roots can efficiently absorb moisture to transfer to the leaves to prevent bruising.
If you water too lightly, the soil will become damp on the surface and the water won’t go to the fern’s roots where it is needed.
3. Small Pots Dry out Too Quickly Cause Brown Leaves
A fern’s roots can deplete the potting soil of nutrients and grow so large that they need more water than the soil can hold if it has been in the pot for an extended period of time.
It’s also crucial to keep in mind that fern roots tend to grow broader rather than deeper naturally, so if your fern is in a tiny pot, the roots may quickly become pot-bound.
Because of their shallow, wide root systems, ferns do best in pots that are roughly as wide as they are deep, or even somewhat wider and shallower.
How to Fix It
Typically, ferns need to be repotted every one to two years, so occasionally check to see if the roots are pot-bound by removing some of the top soil, and repotte your fern into a pot with a minimum diameter of an inch bigger.
Use fresh potting soil instead of older dirt, which may be more degraded and less able to hold moisture. Fresh soil also offers more nutrients.
While ferns can be grown in a variety of pots, they typically do best in unglazed clay pots because clay is a porous substance that promotes more equal soil drying, which offers the ideal environment for ferns (ferns grow in soil that is moist, but not saturated).
Root rot issues, which are more likely to arise in impermeable plastic pots, are much less likely to occur in a pot that dries out more evenly. In order to allow excess water to drain after watering, make sure the pot has drainage holes in the base.
A larger pot allows the soil to hold onto moisture around the roots, giving the fern greater access to the nutrients and moisture it needs to keep its leaves from turning brown and withering.
To encourage the growth of new, healthy, green leaves, trim any brown, crispy, dying leaves back to healthy growth using a pair of sharp pruners (since the individual brown, dead leaves will not regenerate).
4. Too Much Sun (Ferns Grow in Full Shade)
Under a woodland canopy with filtered light or complete shade, ferns naturally grow. When the fern is exposed to excessive sunlight, the leaves lose water more quickly than the roots can take it in, which causes the leaves to become brown and crispy and look to be dying.
All ferns have been carefully modified to thrive in the shade or with some filtered light under the woodland or forest canopy.
This indicates that they are quite susceptible to direct sunshine, which can dry up the soil and cause the leaves to turn brown if exposed to it too soon.
In addition to decreasing humidity and raising temperature around your fern to an unfavorable high range, too much sunlight is likely to do both, which can all contribute to the fern becoming brown and dying back.
How to Fix It
To keep your fern healthy, place it in the shade or somewhere with filtered light.
Ferns can be moved to a shadier area in the house or garden because they are naturally accustomed to the shadow, making them very adaptable houseplants and suitable for shadier gardens.
Although removing your fern from direct sunlight is an excellent place to start, it is crucial to undertake the following things in order to save your fern:
- Ideally, a plant humidifier should be used to increase the humidity around the fern.
- To keep the soil moist but not saturated, water the fern as often as necessary.
These are the best ways to save your fern because it is probably dry and suffering from a lack of humidity as a result of too much sun exposure.
If your fern does not recover, remove any brown leaves or leaflets to encourage healthy new green growth.
5. High Temperatures Cause Fern Leaves to Turn Brown
If the temperature in an indoor space exceeds 80°F for a lengthy period of time, ferns get brown. 65°F to 75°F is the ideal temperature range for ferns. In hotter weather, the fern may lose more moisture from the leaves than it can store at the roots, turning brown and appearing to be dying.
Despite being native to tropical regions, indoor houseplant ferns have very particular temperature requirements that are on the chilly side. Generally speaking, ferns like daytime temperatures of 65°F to 75°F and nighttime temperatures that are around 10 degrees colder.
This is due to the fact that ferns prefer to thrive in protected, shady sections of woodland or forest habitat, where there is typically little direct sunlight and a generally mild climate.
The most common definition of room temperature is 68°F (20°C), but this can vary significantly depending on your climate and the particular room.
The frigid Winter months, when central heating is activated and temperatures in the evening can rise significantly, are when high temperatures are most frequently an issue. Fern stress is a result of these significant temperature swings.
High temperatures speed up the rate of evaporation from the soil and the pace at which ferns transpire (lose moisture from their leaves). Additionally, the fact that temperature swings and high temperatures occur in the evening, when it usually turns colder in their original woodland home, is at odds with the climate there.
The browning of the ferns’ leaves, an indication of stress, is the outcome of all these circumstances. The leaves may also become crunchy and dried out and fall off.
How to Fix It
Place your indoor fern in a space with a 65° to 75°F temperature range. Due to its naturally higher humidity and often cooler temperatures than other rooms in the house, bathrooms are typically the ideal rooms for indoor ferns.
Avoid placing your ferns next to any heat sources or in the air current of a forced air system since ferns like a room temperature at night that is about 10 degrees colder than the daytime temperature.
I must repeat again how crucial it is to keep your fern’s soil moist and at a relative humidity of around 40% for it to recover from any form of stress that has caused the leaves to turn brown.
Any brown foliage should be cut back because it rarely grows back. Getting rid of the brown leaves encourages the development of fresh, wholesome, green leaves.
6. Outdoor Fern Turning Brown (Transplant the Fern)
Brown fern leaves need to be cut back in the winter. This is simply the normal cycle of outdoor ferns throughout the year and does not indicate that the fern is dying.
Ferns are extremely sensitive to full sunshine, which dries out the fern and causes the leaves to turn brown and crispy, or dry, sandy soil that drains too quickly.
How to Fix It
At the end of the Fall season, trim the leaves back when they begin to brown since they are unable to photosynthesize anymore. This neatens up the fern’s appearance and enables you to mulch the fern’s underground rhizomes with compost to help keep them warm over the winter. The fern should recover healthily the following spring.
When growing ferns in sandy soil that dries out too fast after rain or irrigation, add heaps of compost, leaf mold, or well-rotted manure to the planting area.
These three materials all have a porous structure that allows extra water to flow away from the roots, preventing root rot even though they retain a lot of moisture.
As ferns cannot withstand excessive amounts of direct sunshine, always plant them in locations with shade or some filtered light. Either move the fern to a more shaded area or grow additional trees or bushes to provide shade.
- Low humidity and drowning lead fern leaves to become brown. Ferns are tropical plants that require high levels of humidity. Indoor humidity is frequently too low, which causes the leaves to lose moisture and turn brown, crispy, dried out, and look to be dying.
- Due to submersion, fern tips become brown. The soil must be continually damp, but not saturated, for ferns to grow. The fern’s leaves get brown and crispy at the tips if the soil dries up in between waterings because there isn’t enough moisture surrounding the roots.
- Smaller pots dry up faster. Because ferns require continually moist soil, their leaves will turn brown and brittle and will appear to be dying if the potting soil dries out. Because ferns often have large, shallow root systems, they can easily become pot-bound in small pots, which can turn their leaves brown.
- In much sunshine, fern leaves oxidize and turn brown. Ferns may survive in either complete shade or partial light beneath a woodland canopy. The delicate leaves become crispy and brown in full sun, appearing to be dying.
- If the temperature is over 80°F for a prolonged period of time, indoor ferns may turn brown. Ferns favor temperatures between 65°F and 75°F. The ferns’ leaves become brown and crispy and appear to be dying in high temperatures because the leaves lose too much moisture and the soil dries out too quickly for the roots to pull in moisture.
- In the Fall, just before Winter, outdoor ferns naturally turn brown and appear to be dying. The following Spring, the fern sprouts fresh, green leaves. If the ground is too dry or there is too much sun, outdoor ferns may also turn brown. To keep its leaves from turning brown, outdoor ferns need moist soil and shade.
- Use a humidifier to raise the humidity, water as often as necessary to keep the coil consistently moist, stay away from drafts and indoor heating, place the fern in an area with indirect light, make sure the temperature is between 65°F and 75°F, and cut back brown leaves to encourage the growth of new green leaves in order to save ferns with brown leaves.
Should you cut brown leaves off ferns?
Brown fronds should constantly be pruned down; this is good practice for the plant. It not only enhances the fern’s look but also lowers the danger of disease and promotes fresh, healthy growth.
Can ferns come back after browning?
Since most ferns are hardy plants, once the problematic conditions are fixed, they usually recover within a few weeks. The good news is that the fern will grow again in spring once the temperatures rise, even if it is dead now, which is typical in frigid temperatures during winter.
What does an overwatered fern look like?
Yellowing or wilted leaves are frequently the first indication when a fern is overwatered. Touching the dirt with the tip of your finger is a guaranteed technique to tell when to water a Boston fern. It’s time to water the plant if the soil’s surface feels a little bit dry.
How do I know if my ferns will come back?
Setting up ideal circumstances for recuperation and then waiting to see if new growth materializes are the only surefire ways to determine whether your fern is still alive. The length of time required will depend on the season, with springtime likely seeing the fastest recuperation (especially for deciduous ferns).
What happens when you overwater ferns?
Overwatered ferns may develop yellowed leaf, wilting, or eventually fungal illnesses or root issues. Your ferns will wilt if they are submerged. When they don’t get enough water, Boston ferns are especially susceptible to lose their leaves.