Why Are My Monstera Leaves Turning Brown?

Last Updated on March 19, 2022 by Admin

Monstera are best known for their large, fenestrated leaves. These are stunning to look at and make an instant impact in any home. However, there may come a time that these lovely leaves turn brown. And when they do, it becomes a cause of concern that you need to immediately deal with.

Why are your Monstera leaves turning brown? Monstera leaves turn brown when the plant is struggling with something. The most common causes include overwatering and excess sunlight. Overwatering can develop into a serious problem because it makes your Monstera prone to root rot. Other possible causes of brown leaves including low humidity, infection, temperature stress and underwatering.

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Why Are My Monstera Leaves Turning Brown

Monstera leaves turning brown is a sign that the plant is not getting what it needs. There are usually a few reasons why this happens. And it is your job to diagnose what the root cause of the browning is.

Below I’ll go through the different possible causes, why they happen and how to fix each one. This way, you can identify the source of the issue by process of elimination.

Overwatering is the #1 Cause for Monstera Leaves Turning Brown

The most common cause for Monstera leaves turning brown is overwatering. When this happens, you’ll notice brown spots appearing on the leaves.

Overwatering is a common problem because many growers and houseplant owners use a fixed schedule to water their plants.

If you live somewhere with consistent weather, this is not too much of a problem. However, in most cases, the weather changes throughout the year as the seasons change.

Therefore, how long it takes for the soil to dry will likewise vary.

During the summer when the weather is warm and the sun is out, you’ll need to water more regularly since soil tends to dry faster.

However, as the weather cools down in autumn and even more so in winter, it takes longer and longer for the soil to dry due to the cold temperature and decreased sunshine.

So, if you stick to a fixed schedule all year round, you’ll end up underwatering your Monstera during the hottest times of the year and overwatering it during the cold season.

Dark Brown Spots from Overwatering

Monstera plants enjoys slightly moist soil. But they hate wet feet. And if their roots are left to sit in water for extended periods of time, it can lead to root rot.

In most cases, overwatering is caused by a few things, all of which you should try to avoid.

Watering too often
Using soil that is heavy or retains too much water
A pot with no drainage

When any of these factors occur, the plant’s roots will end up sitting in water for prolonged periods of time.

As a result, you’ll start seeing brown leaf spots.

Risk of Root Rot

If the issue goes untreated, it can eventually lead to root rot. This occurs when the roots get damaged and start rotting. As a result, they’re not able to absorbs water or nutrients from the soil anymore.

This becomes a huge problem for your Monstera because it won’t be able to get sustenance.

Thus, over time, the plant will deteriorate in health, start wilting, dropping leaves and eventually die.

For this reason, it is very important not to overwater your Monstera. The simplest way to adjust your watering schedule based on what the plant needs.

You can do this by checking the soil regularly. Once the top 2 to 3 inches of soil dries up completely, you can water the plant. But never before that. Doing so will help prevent overwatering.

Similarly, using chunky, well-draining potting mix will prevent waterlogging. This kind of soil will hold just enough moisture for the plant’s roots. More importantly it drains excess moisture to avoid letting the roots sit in water for long periods of time.

Finally, making sure the that pot you sue has drainage holes allows excess liquid to escape from the container. This prevents water from pooling at the bottom of the pot which keeps the soil wet.

Too Much Direct Sunlight

Another reason for Monstera leaves turning brown is excess light.

Monstera plants are native to tropical rainforests. There, they live under the canopy of very large trees.

As such, while they do get some sunlight, they do not get a lot of direct sunshine. That’s because the leaves and branches of larger plant block out the sun.

As such, the plant is used to getting dappled, diffused or filtered light. More importantly, it means that your Monstera cannot tolerate direct sunlight or very intense sun for prolonged periods of time.

If placed in a such an environment, the leaves will get sunburn and turn brown.

Therefore, the best location for your Monstera are:

Indoors – somewhere with medium to bright, indirect light
Outdoors – somewhere with partial shade

The key is to keep the plant away from the direct rays of the sun especially during the hottest times of the day (11:00 a.m. to 3:30 p.m.). Similarly, avoid leaving it under strong sun during summer.

This makes a south-facing window not ideal for your Monstera. If you want to keep it there, make sure to distance it from the window (at least 3 feet away) or filter the light with curtains or blinds.

Fortunately, it is easy to solve brown Monstera leaves caused by excess light. All you need to do is move the plant to less bright spot and it will recover.

Lack of Humidity

Another important aspect of Monstera cares is humidity. Since the plant comes from tropical regions, it is used to warm and humid conditions.

The ideal humidity for Monstera is between 60% and 80%. Although, it will do well as long as humidity stays at 40% or higher.

This can make it challenging to care for indoors depending on where you live.

If you live in a tropical region or near a body of water like a like, then humidity should not be a problem. Similarly, if you keep the plant in a greenhouse, you’ll be able to control air moisture.

However, other areas are less suited due to dry air, this includes desert or desert-like locations. Also, very hot summers or cold winters tend to dry the air.

Thus, if humidity tends to drop under 40% where you live, it is important to keep an eye out for these times. When the Monstera does not get enough humidity, its leaves can turn brown.

As such, it is a good idea to be aware of when this happens and increase humidity around the plant. You can do so by:

Using a humidifier
Misting the plant a few times a week
Move the plant to the bathroom
Give it a shower every 2 weeks or so
Put it on a pebble tray

Related

Underwatering

Monstera leaves turning brown can likewise be caused by lack of moisture. When this happens, you’ll see the leaves turn brown beginning at the tips and edges.

That’s because water pressure is weakest at the farthest extremities which are the borders and tips of the leaves. So, when the plant is short of water, it is these parts that get dehydrated first.

If underwatering persists, the leaves will start shriveling up. They will also curl and get crispy and brittle.

When you see these symptoms occur, the first thing to check is the soil. If the plant is suffering from lack of water, the soil will be very dry. In many cases, it will be bone dry.

The good news is that fixing an underwatered Monstera is much easier than an overwatered one.

Once you’ve confirmed from the soil that it is indeed lack of moisture that’s the cause of the brown leaves, all you need to do is add water.

You can do so in two ways.

Water the soil – add water to the soil until it gets saturated. For larger plants, you can leave a hose on the rim of the pot to let it soak the soil. Try to add water in different parts of the soil not just in one area. Once the liquid begins dripping from the bottom drainage holes, stop. Then, let the soil drain.
Use bottom watering – with bottom watering, you can fill a bucket that’s larger than the pot with water until about a quarter full. Then place the pot in the bucket. The soil will start absorbing water from below. This will take between 15 to 30 minutes depending on how big your plant is. Then remove the pot from the bucket and let it drain for another 15-30 minutes.

Once watered, it only takes about 24 hours or so for your Monstera to perk up.

You can then remove the brown leaves. Cut off the leaves that are more than 50% damaged. For the rest, you can reshape them.

Make sure to adjust your watering routine to avoid this from happening again.

Fungal Infection

If you notice brown spots with yellow rings around them appearing on your Monstera’s leaves, there’s a very high likelihood that it has fungal infection.

Fungus growth is a big problem with houseplants when there’s too much moisture. As such, be careful not to overwater your plant or mist it too much.

Also, make sure there is sufficient air circulation to allow any wet spots to dry up faster.

The longer leaves or soil stay wet, the higher the chance of fungal infections.

Unfortunately, if the infection is not treated, you’ll eventually see entire leaves turn brown and then fall off. Over time, more and more leaves will follow suit.

With fungal infections, you have a few options.

Let the plant dry – moisture is what allows the fungal infection to grow, develop and spread. By moving allowing the plant to stay dry more, it makes the environment unhospitable for the pathogens to survive.
Avoid overwatering and too much humidity – these are the two potential causes of fungal and bacterial infections. By reducing this, you not only prevent them but also stop them from spreading.
Prune or reshape damaged leaves – depending on how much damage each leaf has sustained, you can either cut off the affected sections or the entire leaf.
Spray the affected areas with fungicide – this is usually your last resort. I like to deal with infections the natural way as opposed to using commercial products. But if the problem persists, do use fungicides to treat your plant.

Temperature Stress

As mentioned above, Monstera are tropical plants. Thus, they enjoy warm, balmy weather. And they can even tolerate hot climates with no problem.

However, since tropical regions have sunshine all year round, the plant is not accustomed to the cold, winters, snow or frost.

In fact, it is not frost hardy and cannot tolerate freezing temperatures.

As such, avoid leaving the plant in temperatures below 55 degrees Fahrenheit. Instead, try to keep it in its ideal temperature range of 60 to 80 degrees Fahrenheit.

If the plant is left in cold conditions for long periods of time, you’ll see its leaves turn brown. They will initially present with brown spots. But as it gets colder or they stay there longer, your Monstera will sustain cold stress, injury and damage.

As things get worse, you’ll eventually see leaves die and drop off. The plant will also struggle then deteriorate.

Therefore, if you live below USDA Hardiness Zone 10, make sure to bring the plant indoors once the weather drops to 55 degrees Fahrenheit.

Indoors, be wary of air conditioners and cold drafts as the plant does not appreciate sudden drops in temperature either.

Water Quality

Monstera are generally not very sensitive to minerals in water like other houseplants. However, if you’ve gone through all the other possible causes and struggle to find an explanation for the browning leaves, consider checking your tap water.

Some cities add more chemicals to their tap. The reason for this is to make the water safe for drinking.

However, these chemicals including fluoride and chlorine can be toxic to plants in excess amounts.

As such, if your locale’s tap produces hard water, it could cause your Monstera’s leaves to turn brown.

The best way to tell is to check with your municipality to see how much chemicals are added and whether or not it is actually the cause of your browning Monstera plant.

If so, you have a few options.

Use filtered or purified water instead of tap water
Collect rainwater and use that to water your plants. You can set up a rain barrel to do this.
Continue using tap water. But before you use it, allow it to sit at room temperature at least overnight. This will allow the chemicals to evaporate before you water your plants.

Lack of Nutrients

Nutrient deficiency is another cause for Monstera leaf discoloration. In many cases, the leaves will turn yellow. However, lack of nutrition can also turn Monstera leaves brown.

As such, it is important to make sure that the plant is getting enough nutrients.

This can either be from the soil by adding compost or using a rich potting mix. Applying fertilizer is likewise beneficial since it helps your plant grow faster and produce more leaves.

With the latter, make sure not to overfeed your Monstera as this will cause a host of other problems since fertilizers contain soluble salts than can be toxic to plants when enough of it accumulates in the soil.

How to Fix Brown Leaves on Monstera Plant

The best way to fix brown leaves on Monstera plants is to figure out what the cause of the problem is and treat it.

In most cases, it is overwatering. However, there are other possible causes as listed above. Therefore, go through them one by one and use the process of elimination to narrow down the cause.

Here’s a simple guide you can follow.

Check for watering issues. You can do this by sticking your finger into the soil. If it feels wet, the plant is likely overwatered. Therefore, allow it to dry. If the soil is very dry, add more water.
Next, check for humidity. Try to keep humidity at 40% and higher. If not apply the humidity increasing measures listed above.
If moisture is not the issue, see if the plant is getting direct sunlight. If so, move it to a location with medium to bright, indirect sun.
Always make sure that the plant is not left anywhere colder than 55 degrees Fahrenheit. If so, move it somewhere warmer.
Finally, check the plant, its leaves, stems and soil for any signs of pests or disease. Treat them immediately if you spot any.
Once you’ve diagnosed the problem, you can now trim off or reshape the affected leaves.

Frequently Asked Questions About Monstera Leaves Turning Brown

Should I Cut Brown Leaves Off Monstera?

Yes. You should prune off the damaged leaves of your Monstera. However, because the leaves are large, you don’t necessarily have to cut off the entire leaf. Instead, for those with only small damages, remove the affected sections including brown, black or yellow portions of the leaves.

How Do You Fix Brown Monstera Leaves?

To fix brown Monstera leaves, make sure that the plant is not overwatered. This means waiting until the soil is 50% dry before adding more water. Adding water too frequently increases the risk of overwatering. Also, make sure to maintain at least 40% humidity.

Is My Monstera Overwatered or Underwatered?

Yellow and brown leaves on Monstera often mean the plant is either overwatered or underwatered. Both can happen at different stages. Therefore, the best way to make sure is to check the soil. Very dry soil means your Monstera lacks water. Wet, soggy soil means it is overwatered.

What Helps an Overwatered Monstera?

Overwatering can lead to root rot. Thus, make sure to check for root rot first if you suspect overwatering. If there is root rot present, the best thing to do is repot the plant in fresh, dry potting mix. If there is no root rot, allow the soil to dry before adding more water. Then adjust your watering schedule.

Should I Mist My Monstera?

Misting helps your Monstera if humidity is not high enough. Try to maintain humidity of 40% or higher to keep your plant healthy and happy. However, avoid over misting your plant since wet leaves can lead to fungal infections.