The maidenhair fern is native to North America and is one of the most popular ferns to be kept as a houseplant. It has thin black stems that produce fan-shaped leaves which are much smaller than those of most other ferns. Along with its compact size, this makes it an easy fern to grow indoors.
The maidenhair fern typically takes three or more years before it can be considered fully grown, and because it is not the hardiest of plants, it cannot be grown just anywhere outdoors.
One of the most common problems encountered by maidenhair fern owners is when their plants’ leaves turn brown, which is due to an environmental factor causing the plant stress.
The possible causes of this discoloration are temperature extremes, too much sunlight, not enough water, low humidity, incorrect soil, too much fertilizer, overcrowding, and the natural aging of the plant.
In this article, we will discuss each of these causes and what you can do to resolve them. So, if you are experiencing a similar problem and you need some guidance, just keep reading.
Why are the leaves on my maidenhair fern turning brown?
Temperature extremes
Hotspots are a common cause of brown leaves on maidenhair ferns. This occurs when your plant is located right next to a window, where the sun’s rays can dramatically increase the air temperature around the plant. If your maidenhair fern is growing too close to a radiator or heating vent, this can also result in hotspots and browning of the leaves.
Pick up a digital thermometer to keep track of temperature changes throughout the day; this will help you determine whether your plant’s brown leaves are the result of extreme temperatures.
To fix leaf browning caused by temperature extremes, all you need to do is relocate your maidenhair fern to a place in your home where the temperatures are more stable. The plant will then not dry out as quickly and the leaves should stop turning brown.
Too much sunlight
The maidenhair fern is a tropical plant with a fern-like appearance, and it prefers diffused light in the daytime. If subjected to direct sunlight, it will develop brown leaves and, if not relocated soon enough, it can die.
Maidenhair ferns can be grown in semi-shade below trees, or in a cool environment either indoors or out in the yard or garden. If you keep your plant indoors, place it next to an east-facing window. If this is not possible and the only window available lets in harsh light, hang a sheer curtain over the window before placing the plant on the windowsill. Rotate the pot a few degrees every five days so that all sides of the fern get their share of light and the plant grows symmetrically.
If you have just moved your plant to a shadier spot to remedy its browning leaves, also check the moisture of the soil in the pot: it may have dried out faster than usual if it was over-exposed to sunlight. If the top two inches of soil are dry to the touch, water the plant, but if the soil is still damp, wait one or two days before checking it again.
Not enough water
Another factor that can contribute to brown leaves is repeated underwatering. Because their stems and leaves are so delicate, maidenhair ferns require consistent moisture in their soil and will struggle if the potting mix becomes too dry. You need to be extremely vigilant about keeping up with their watering schedule, as their leaves can start browning very quickly.
If your maidenhair fern is suffering from a lack of water, rather than watering it generously once a week, slowly reintroduce water to the plant. Water it once a day for a week, and it should be able to recover from the dehydration.
Low humidity
A lack of humidity is usually the first thing to look for if your maidenhair fern develops brown leaves. Because the leaves are so fragile, they are more sensitive to low humidity than most other houseplants.
In the winter, when heating and reduced ventilation cause the air in our homes to become extremely dry, maidenhair ferns can have a difficult time surviving. If your plant’s leaves turn brown for this reason, do not worry; there are some very simple and inexpensive solutions that will instantly restore their freshness.
A daily misting of the leaves with water will keep them from becoming dry. Do this first thing in the morning so that the water can evaporate off the leaves throughout the day, before the temperature begins to drop in the evening. The presence of moisture in the leaves when the temperature drops can cause them to rot, which is best avoided.
Showering your maidenhair fern is another simple way to instantly increase the humidity around it and prevent its leaves from turning brown. In addition to getting rid of dust and potential pests that may be on your plant, try washing it down with water every few months, regardless of whether or not its leaves are brown. However, avoid using extremely hot or cold water when you do this, because that will shock the plant and can cause its leaves to burn. Furthermore, the water pressure should be low, because these plants have extremely delicate leaves and stems.
Keeping your plant fern in your kitchen or bathroom is a good idea, because these are the most humid rooms of a house. The steam produced from showering and cooking keeps the humidity higher than in other parts of the house.
If you have the means, you can also purchase a humidifier. This is the simplest, most convenient way to maintain a consistent humidity level around your maidenhair fern and keep its leaves from browning.
Incorrect soil
If your plant develops brown leaves, it is possible that soil quality is a factor. A slightly acidic soil that is loose, airy, yet still able to retain some moisture, is what maidenhair ferns prefer. Added media such as composted soil and peat can be used to maintain the soil’s slight acidity and water retention properties.
It is also important not to plant your maidenhair fern too deep in the soil, and there must be drainage holes at the bottom of its pot. Good drainage is essential so that if you pour too much water into the soil, any excess will simply flow out of the drainage holes. This keeps the soil from becoming waterlogged and soggy.
Too much fertilizer
You should only fertilize your plant once a month, and only during the growing season. Do not feed it during its dormant season. If you are fertilizing your plant more frequently than this, or if you are not diluting the fertilizer, this could be the reason its leaves are turning brown.
If you suspect that overfertilization is the reason for your plant’s brown leaves, you may need to flush the soil with water. Take your plant to your sink and pour water generously over all of the soil in the pot. You need to repeat this flushing process four times, at intervals of 10 to 15 minutes, each time using a volume of water four times the volume of the plant’s pot.
Overcrowding
If a maidenhair fern’s roots become overcrowded in their current container, the plant is likely to die unless you act promptly. This plant should be repotted every couple of years to ensure that it continues to thrive. If necessary, divide it by cutting between its fleshy roots, known as rhizomes, ensuring that you keep an equal number of leaves on each section that you separate.
Overcrowding occurs when a plant’s roots completely fill the pot. They will then start growing out of the drainage holes or over the top of the soil, and water will drain directly through the pot and out of the drain holes instead of soaking into the soil.
If you believe your fern is overcrowded, transplant it to a larger pot or divide it in the spring, just before new growth begins.
Natural aging
If your maidenhair fern develops a few brown leaves here and there, do not worry; this is completely normal. Your plant is simply getting rid of some of its older leaves so that it can focus on growing new, healthy leaves.
Since this is a naturally occurring process, there is nothing you need to do except to continue caring for the plant as usual. If you find the brown leaves distracting, you can remove them one by one using your clean fingers.
Maidenhair fern care
Light requirements
Maidenhair ferns grow in a forest environment where they are mostly shaded by a canopy of trees and receive only a small amount of direct sunlight on bright, sunny days. If you want to successfully grow this fern indoors, try to replicate these conditions by placing it in a location in your home that receives only indirect sunlight.
Avoid using direct sunlight or harsh lighting for your maidenhair fern, because its delicate leaves are prone to burning. A lack of light, on the other hand, results in poor growth and yellowing fronds. Make an effort to find that perfect spot that receives indirect morning or afternoon sunlight, such as a north-facing window.
Soil requirements
Maidenhair ferns prefer a moist but well-draining potting mix. As previously stated, water is extremely important for this plant, so to help create the ideal environment, incorporate moss or organic matter such as compost into the soil to aid the retention of water.
Water requirements
To ensure that your thirsty maidenhair fern thrives, make sure that you water it every day or, at least, every other day. This plant likes its soil to be moist at all times but be careful not to give it too much water, because it can still become overwatered despite its love for moisture. Keep an eye out for yellow leaves, which can occur as a result of overwatering. Never allow the plant’s roots to stand in waterlogged soil; water it only when the top inch of soil is dry to the touch to maintain the degree of moisture the plant prefers.
Temperature and humidity requirements
Keep your maidenhair fern in a room where the temperature is between 60 and 70 degrees Fahrenheit. It likes humidity, and will struggle where the air is dry. If you have the means, it may be a good idea to buy a humidifier to regulate the humidity in the room where you keep your plant.
Conclusion
The Maidenhair fern is a beautiful plant native to North America. It has delicate, fan-shaped leaves that grow on thin, black stems.
Because of its compact size and delicate foliage, the maidenhair fern makes a great indoor plant. Also, it is slow-growing, so it does not need to be repotted very often.
One of the most common problems in maidenhair ferns is when their leaves turn brown. The most probable causes of this are temperature extremes, too much sunlight, not enough water, low humidity, incorrect soil, too much fertilizer, overcrowding, and natural aging.
The sooner you are able to determine the exact cause of the browning leaves, the faster you can remedy the issue and return your plant to full health.
Image: istockphoto.com / Puripat penpun