Boston Fern Keeps Turning Brown? How To Fix It

The Boston Fern is a timeless plant that, with proper care, will thrive for over 100 years. Unfortunately, a common issue with Boston Ferns is browning leaves, which are signs of underlying problems. So what is the primary cause of leaf browning, and what can you do to fix it? 

Boston Ferns keep turning brown due to poor soil quality, lack of moisture, inadequate lighting, and outgrowing its pot. Easy fixes include regular watering, placing in indirect sunlight, and repotting into a larger pot with better soil. Identifying the main issue will help you choose the best fix.

In the rest of this article, I will discuss in great detail why Boston Ferns turn brown, ways to fix browning, and preventive measures you can take against future issues. So if you want to learn more about keeping your Boston Fern healthy and brown-free, read on.

Common Causes of Boston Fern Leaf Browning

Boston Ferns turn brown for several reasons, and if left unchecked, browning can lead to the death of your plant. The most likely cause of browning in your fern is neglect. It’s easy to miss a care requirement for your fern since they generally require so little care. 

Luckily, the reasons these ferns brown are relatively simple and can be remedied with relative ease if you’re proactive. But first, you simply need to get to the bottom of what is causing your Boston Fern’s leaves to turn brown. 

Poor Soil Quality

One of the biggest reasons Boston Fern plants struggle is a lack of nutrients in the soil. Unfortunately, poor soil quality occurs regularly since these plants live for a long time. As a result, the nutrients get depleted and aren’t replaced, leaving the fern to struggle, often presenting symptoms like brown leaves. 

These ferns want soil rich in organic matter and loamy with good drainage. The plants also thrive best with an acidic pH between 5 and 5.5. Typically Boston Ferns need their soil replaced every 2-3 years to maintain optimal plant health. 

Improper Drainage

Another primary culprit for browning Boston Fern leaves is a lack of drainage. Ferns that are placed in pots doubly require good drainage. Otherwise, water builds up on their root system and causes rot. The rotting process of the roots is more commonly known as root rot

Early signs of root rot include dehydrated and browning leaves. This is because the damaged roots can’t deliver enough moisture up to the shoots. 

As the name suggests, this disease attacks the plant’s roots and begins to kill them. The injured and eventually dead roots cannot absorb nutrients from the soil, resulting in the plant’s death. So without proper drainage, your fern is more susceptible to this condition.

Inadequate Water

If it’s not a drainage or soil quality issue, then there is a good chance the plant isn’t getting enough water. Because Boston Ferns are low-maintenance plants, it’s easy to forget them and skip watering. However, regularly skipped watering will result in brown and crunchy leaves. 

Boston Fern requires a lot of water compared to other house plants because the ferns always prefer their roots to be moist but not soggy. Therefore, if your fern is outdoors, it will need watering daily, especially on warm summer days. 

However, an indoor plant will require less attention and typically only requires weekly watering. You want to allow the top 2 inches (5 cm) of soil to dry before adding more liquid. Depending on your home’s temperature and the climate you live in, how often you need to water the fern will vary. However, the soil is always a good indicator. 

Also, humidity is a factor you want to consider, as plants like the Boston Fern also require plenty of moisture in the air to thrive. 

Too Much Sunlight 

Too much sunlight can also contribute to the browning of Boston Fern leaves. The plant fronds are delicate and quickly burned by direct sunlight on warm days. Placing the plant directly next to a window is an excellent way to burn its leaves, as these ferns prefer indirect sunlight. 

Sunlight can destroy the cells in the plant’s leaves, causing them to break down and turn brown. Brown leaves will struggle more to absorb light, making the plant ill since the fern will still need sunlight, albeit indirect, to create plant food. 

Temperature Issue

Sometimes the temperature around the Boston Fern causes leaf browning because temperature plays a huge part in the fern’s overall health. Like sunlight, exposure to too much heat can cause a fern’s leaves to become brown and dry. 

Boston Ferns prefer temperatures between 68 and 77 °F (20 and 25 °C) and will severely struggle when temperatures hit above 90 °F (32 °C). 

Places in the home, like near vents or windows, often exceed the fern’s temperature needs. Windows create heat and drafts throughout the year. On the other hand, vents can blow concentrated warm and cold air on the fern. 

Pot-Bound Roots

Your plant might develop brown leaves when it becomes rootbound. Over time, the root system grows into every possible space within the container. There’s no more room for the plant to spread out. Plus, most of the nutrients have likely been consumed already. As a result, the foliage will show signs of distress, including turning brown.

Repotting your fern every 2-3 years can prevent this. Moreover, the soil likely needs fresh nutrients and the roots need more room. 

Plant Injury

Lastly, your Boston Fern’s leaves might turn brown due to an injury. These ferns are large plants with long leaves that hang down. The fern isn’t a strong plant and its leaves are delicate. Therefore, frequent foot traffic near them makes it easy for some of these leaves to become damaged. 

Additionally, some pets, like cats, enjoy chewing on the leaves. The chewed portion of the leaves will turn crispy and brown. So it’s best to place your ferns somewhere that they won’t be bumped or gnawed on. 

8 Effective Fixes for Browning Leaves

Now that you understand more about the likely causes of browning leaves in Boston Fern plants, it’s time to discuss the fixes. The plant is pretty hardy but will struggle when one or more needs are continuously unmet. 

So how can you fix your fern if its fronds keep turning brown? 

1. Check the Temperature 

First, you must check that your Boston Fern is kept at the correct temperature. You want to move the plant away from any large windows where direct light will hit them. Also, check that no air vents are blowing directly on the fern. Additionally, it helps not to place the plant in a hot or cold room. 

Boston ferns thrive in temperatures also comfortable for your family members. As long as you keep indoor temperatures around 70 °F (21.1 °C) all year round, your Boston fern will grow fresh, green fronds.

You can more easily monitor the temperature using a gauge and adjust it as needed. Depending on your home’s temperature throughout the year, different seasons will also require different placements for your fern. So be proactive in checking the plant’s temp needs as the seasons change. 

2. Get the Fern on a Watering Schedule 

Another way to help your browning fern recover is to get it on a watering schedule or at least check the soil regularly. As discussed, Boston Ferns require plenty of water, but that water can’t sit on its roots. 

So when watering, it’s essential to check the plant’s soil for moisture. Typically the first few inches or so should be dry before adding in new water. Generally, you should water your fern at most once per week if it’s indoors. 

However, the environment plays a huge role in water needs, and so does your plants’ container. Do what you feel is best after investigating the moisture in the soil, and at least create a schedule to check on your plant. You can put it into your phone’s calendar as a reminder, so you remember. 

Additionally, bottom watering a plant prevents overwatering from occurring and ensures the plant gets enough to drink. You can place the pot in a tub of water and allow the soil to absorb moisture from the drainage holes at the bottom. After about an hour, the plant will have absorbed all it can. 

After a few weeks or months of improved watering routine, you will notice your Boston fern growing new and healthy fronds.

3. Provide Adequate Humidity 

Regular watering is bound to help your Boston Ferns brown leaves, but with moist soil, it’s also essential to pay attention to the humidity levels in the room. Boston ferns thrive at about 50% humidity. However, in a home, this level of humidity isn’t always feasible. 

Therefore, you must employ some ways to increase the humidity around your fern. Below are a few tips:

  • Mist the plant a few times per week. 
  • Place a humidifier nearby. 
  • Place a pebble tray with water under the plant’s pot. 
  • Place the plant in your bathroom

These are all great ways to raise the humidity around your fern. However, you still need to ensure you’re not overdoing it with the humidity to prevent mold or fungi growth, which is why a temperature/humidity gauge is an excellent investment. 

4. Repot the Fern

All house plants need to be repotted occasionally, and the Boston Fern is no exception. These ferns grow at a steady pace and tend to live long lifespans. Potted ferns need to be repotted every 2-3 years to ensure optimal nutrients in the soil and space for the roots to grow. 

When repotting, you want to upgrade the plant to a larger container with excellent drainage and use new soil that is nutrient-dense. Using a larger pot can reduce the need to repot your plant frequently. Repotting your fern also helps prevent issues like the plant’s roots becoming root bound. 

Adding in healthy soil is also a quick but temporary fix if you don’t have time for repotting. Just be sure to do so carefully. You can also add compost to improve soil quality and introduce slow-release nutrients.

If you haven’t ever repotted a Boston Fern, I suggest watching The Girl with a Shovel’s video on repotting. She does a great job of quickly walking you through the process and showcasing each step. She also gives some great tips as she goes. 

5. Fertilize the Plant 

Another step that can help your fern is fertilizer if your plant’s soil is lacking nutrients. However, it’s essential not to overdo it on the fertilizer as too much can cause the plant’s roots to burn and result in more brown fronds. A slow-release fertilizer will work best. 

Before you add fertilizer, it’s best to test the soil to see what it’s missing. Testing ensures you don’t add too much of one nutrient, making the plant uncomfortable or sick. Most tests on the market come in rapid varieties and are easy to use.

6. Check the Lighting 

Adjusting your Boston Ferns lighting is another excellent way to help with brown fronds. Light is often the culprit for brown leaves, so moving your plant around can be helpful. Boston Ferns prefer indirect light, so place them somewhere with bright, filtered light.

The fern shouldn’t be placed against a window, especially if it’s a south-facing window. Instead, place the fern in the room just out of reach of any direct sun rays. You can also hang white curtains against the windows and glass doors.

If you live in a home with dim lighting, adding artificial light will help. Grow lights aren’t as good as the real deal, but a little help might go a long way for your fern. 

7. Cut Away Dead Fronds

Another step that will help your Boston Ferns with browning leaves is to trim back the dead ones. These fronds are no longer viable and will only weigh the plant down further. Additionally, the fern needs all its energy to focus on repairing the healthy portion of the plant. 

Be careful not to trim away too much of the plant, and do your best to only remove dead foliage. 

8. Move the Plant Somewhere Safe 

If you suspect your Boston Fern is turning brown due to physical damage, moving the plant somewhere safe is best. Areas with heavy foot traffic are less-ideal as the plant is more likely to be bumped or walked into throughout the day. Regular damage will stress the fern out and can even result in plant death. 

Additionally, many areas at home may not be ideal if you have pets bothering the plant. So if possible, find a quiet room with good light to move the plant into. 

Kitchens or bathrooms are suitable for Boston Ferns because they’re less likely to be frequented by pets. They also have higher humidity levels than the rest of the house.

Other safe locations include the guest room or the corner of a sitting room. 

How To Prevent Browning 

The best method to prevent a Boston Fern from browning in the first place is regular maintenance. All plants require maintenance to thrive, and it’s essential to know what your fern requires. 

For example, it’s important to periodically check the plant’s soil, water, and lighting situation. You also need to have a vague idea of when to repot the plant. 

Annual checkups of your fern will also go a long way since you will more quickly catch issues like browning leaves before they develop. Creating a schedule for watering or adding humidity is also helpful in ensuring the fern doesn’t brown in the first place. 

Should I Cut Brown Leaves Off?

You should cut brown leaves off a Boston Fern. Brown leaves are likely dead or dying, and removing those leaves makes way for new healthy plant growth. Along with browning leaves, you also want to remove any other dying plant matter. Dying leaves take away nutrients from the rest of the plant. 

Can Boston Ferns Come Back After Browning?

Boston Ferns can return after browning so long as the entire plant isn’t dead. Browning is usually a sign of the plant’s needs not being met, like water, light, or soil requirements. Bringing a fern back requires patience. Repotting the fern is helpful to refresh the soil and give more space.

Final Thoughts 

Boston Ferns are generally easy to care for, but their fronds can turn brown if they don’t receive adequate care. The most likely culprits of brown fern leaves include the following:

  • Too much sunlight
  • Lack of nutrients in the soil
  • Underwatering
  • Inadequate temperatures 
  • Plant injury

For proper maintenance, remember that Boston Ferns need to be repotted with fresh soil and larger pots every few years. Good watering, proper location, and suitable temperature and humidity management are also vital to the plant’s overall health.

Alexander Picot

Alexander Picot is the principal creator of, a website dedicated to gardening tips. Inspired by his mother’s love of gardening, Alex has a passion for taking care of plants and turning backyards into feel-good places and loves to share his experience with the rest of the world.

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