What Causes Brown Spots on Monstera?

Are you wondering the reason your beast has been spotted with brown spots on its lush leaves? It’s a complete turn-off, isn’t it?

To be honest These spots don’t show up randomly. There are reasons for the reasons they’re showing right now and the reasons we must be aware of, comprehend, and come up with solutions before it’s too late.

Fungal leaf spot diseases as well as insufficient watering are the main reasons for brown spots appearing on the monstera. Other elements like heat, light, humidity and temperature fertilizer, as well as water quality are also cause this issue. It could also result from insects or excessive exposure to direct sunlight. Since this could be an indication of other issues it is important to get them treated as soon as is possible.

For more specific details on the causes that lead to the appearance of brown spots that look ugly on leaves, we’ll need to dig a bit deeper. Continue reading and be sure to take note of everything you read.

How to Identify Monstera Brown Spots?

The identification of brown spots on monstera is a difficult task. It’s easy to misinterpret the spots as normal part of the process of aging.

So I’ve put together an easy guideline to determine whether your beast is being affected by brown spots.

What do they look like?

The first step in identifying brown spots is to become aware of how they appear when you spot them on leaves.

Black to dark brown is the typical shade for these marks. Sometimes, they can also appear reddish or tan and have yellow-colored rings.

Certain spots appear rounded, and others have an irregular shape. Whatever their shape they are referred to as spots.

The size can be small or large, based on the type of damage it causes on the surfaces of the leaves.

Monstera leaves that have brown containers can appear necrotic. Don’t be shocked to notice them falling off their main body or developing smaller leaves more than normal. This indicates how severe the disease is.

What parts in the plants are affected?

Brown spots usually occur in the lower canopy that surrounds the beasta. Shaded areas are more prone to developing brown spots.

The upper or lower surface of the leaves may be covered with brown spots. Sometimes, both surfaces are affected. It is dependent on the cause that is causing the infection.

What Causes Brown Spots on Monstera Leaves?

The appearance of leaves with monstera will reveal the internal physiological issues that are causing them.

Brown spots could be an obvious manifestation of a specific issue with this well-known houseplant. Sometimes, it’s simply a secondary manifestation of another issue.

In this article, you’ll need to be able to determine the factors that cause brown spots on your monstera leaves. To help you understand, look at the following points below:

Excess Light Leading to Scorching

Have you had the experience of getting so excessive exposure to the sun that your skin tanned and it’s almost hurting?

Similar things happen when plants are exposed to sunlight. The wavelengths of light emit ultraviolet radiation which are detrimental to plants when exposure is extended.

Plant cells are prone to burn when the light intensity is excessive. This results in massive brown spots that appear on the surface of the leaves.

The intensity of the scorching is contingent on the severity of damaged cells within.

Two factors can cause scorching. The first is high intensity of light. Another is prolonged exposure to it.

monstera next to white chair in a pot

Temperature and Humidity

The temperature can result in brown spots on leaves , and this can happen in two different ways. If the weather is too dry and hot the monstera could be suffering from heat stress, which causes the plant to die. The leaves begin to show brown spots, and then they become completely crispy and brown.

If it’s cold enough, the leaves of the monstera might develop chill spots as a the result of contact with cold breezes or windows. The spots will appear brown when they are removed.

Humidity however is a catalyst to reproduce pathogens, particularly when it’s high.

They thrive in moist environments. The pathogens, such as fungi, are the primary cause of marking brown spots on leaves.

Pest Infestation

Pests love eating the leaf leaves and sucking the juices out of their tissues, making them their own food.

They can cause wounds that appear as brown spots. If left untreated they could cause severe destruction on the plants.

Insects such as mealy bugs, spider mites, thrips scales, and gnats are common enemies of a monstera.

Certain pests can even harm the plant. If you notice brown spots on your leaves, the pests could be responsible for the problem.

The picture shows thrips in the course of their work. Get rid of the silvering on the leaf’s underside by wiping them clean using a 50:50 mixture of meths and water using the help of a cotton ball.

The silvering will be there because they’ve sucked chlorophyll (green substance) from the plant cells. They are usually found under the leaves of trees.

Leaf Spot Diseases

Bacteria, fungi or other pathogens could be the cause of this leaf spot disease in monstera.

The plants usually contract them through the air or splashes of water on the leaves while the process of watering. The disease manifests on leaves in the form of spots with different dimensions.

Once spores have been removed and settle on leaves, they begin reproducing.

An environment that is prone to infection speeds up the rate of their growth. The first signs of leaf spots appear within a couple of weeks of the infection. (Source: Clemson University)

Rust Causes Brown Spots on Monstera Leaves

Rust is an illness caused by fungi. It’s extremely frequent in ornamental plants such as monstera.

The name is enough to describe it the infection causes an rusty hue on the underside and surface of the leaves. At first look, the leaves may appear to be chlorotic, but they aren’t.

The rust fungi spread across the leaves through the production of powdery spores.

They cause lesions on different parts of the leaves. Sometimes, the lesions mix with each other, forming massive brown spots.

Brown Bumps on Monstera Stem

When I first noticed these brown/black raised bumps or dots in the leaves, one of them has turned discolored, and the leaves’ tips have turned yellow.

In this instance, ensure there aren’t any pests particularly on the back of leaves. When the plant is not tied by poles, loosen the ties a bit and you’ll be scratching at the petriole.

If it is rusty like bumps, then you must start working.

It is a fungal disease that is incredibly difficult to eliminate It nearly destroyed my entire Monstera however, I was able to stop it with the following (though it’s got a lot less leaves).

  1. Isolate right away!
  2. Stop the mist of leaves.
  3. Clean it off using a damp tissue (so you can flush it away)
  4. Every week, apply an excellent rose spray that contains an fungicide to cover all of the stems and leaves (top and the bottom).
  5. The leaves that are badly infected like the ones you’ve seen in your pictures are generally away, so it’s better to cut them off, and preventing any new growth from being contaminated from the already infected leaves.

If you do manage to get rid of it, the discoloration of the leaf generally persists, and you’ll have a spotty leaf.

The plant went through a transition from having 8 leaves to three leaves (due to me taking them away) However, it swiftly produced two stunning beautiful flowers and is now disease-free!

Fertilizer Problems

It is perfectly fine to add fertilizer to keep your plant healthy and lush. Your plant will definitely benefit from the extra nutrients that are added to the soil. However anything that is more than the amount it requires is likely harm the plant.

Fast-release fertilizers, if used in excess, can result in cell burning due to the build-up of salt.

A high concentration of salt near the roots can cause the osmotic stress. This means that cells is released in rapid speed. Cells then shrink and dying.

It’s pretty quick and, within one or 2 days you’ll see those brown marks appearing on the leaves.

If not taken care of promptly, it could result in the abrupt death of a monster. Therefore, it is important to be extremely cautious when it comes to fertilizer application.

Water Quality

We’ve previously mentioned that certain pathogens can be transmitted to another plant via irrigation.

If you’ve had water that’s already contaminated by pathogens and they begin to infect the monstera.

Another issue is that the water used is high in salt content, the plant will have difficulty absorption of rain from soil.

Another cause of stress to the plant. In excess, saline water can cause the cells of the plant to shrink and eventually die. Your monstera may be brown with edges as a sign of the problem.

Outside, you’ll see the leaves turning red or brown spots. Monstera has an intolerant to soils that are salty.

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Incorrect Watering Leads to Browning of Leaves

Being able to supply enough the plants with enough water is a skill that every plant owner should learn to.

The problem is that different plants have how they use water. Therefore, it is important to be aware of the amount of water it requires and when it will require it.

Root rot is a result of watering your monster too much. Check out this article to learn how to help save your monstera from being overwatered.

Water transport and nutrients are affected as a result of this. The next thing you notice is that the leaves begin with brown spots, and eventually they’re everywhere in the plant. As time passes, the leaves begin to turn yellow.

Insufficient water supply can cause burning of leaves, particularly on the edges. If water levels aren’t sufficient it causes drought stress.

The cells begin to lose their vibrancy and swelling because there’s no enough water entering the cells.

How Do You Treat Brown Spots on Monstera?

While leaves with brown spots aren’t an issue however, you must be attentive when you see them grow and spreading.

Treatments must be completed as soon as is possible in order to prevent severe damage. In some cases, monsters could die when left untreated.

Relocate the Plant

Monstera prefers indirect light. If it is in contact with direct, strong light for a long time it is necessary to locate an alternative location for it. If you need to, place an opaque shade over it for security.

You can also modify the lighting conditions inside your house when the lighting source is artificial. lighting source.

Avoid Exposure Extreme Temperatures and Humidity

Be sure to keep it away from the fireplace that has excessive heat coming from windows that are extreme cold or hot depending on the conditions.

Take the plant out of any cold draft source like air conditioners or fans.

It is only necessary to be aware of the current conditions in your home. Be aware of how these extremes could impact your plant’s health generally.

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Manage the Pests Before It Turns Your Plant Down

Pests multiply quickly and within a couple number of weeks, they could cause serious destruction to plants.

If the situation is manageable, the manual removal of pests can work. Be sure to remove the damaged leaves, too.

If the issue is beyond control, you can use a pesticide that is appropriate for eliminating the undesirable organisms.

Be cautious when applying these chemicals to prevent injury. You can also choose natural and DIY solutions at home to cut costs.

Take out the infected plants and put them away from the rest of the plants.

The most important thing is not to spread the disease to other hosts plants. Eliminate the monstera infected when you take care to treat them.

Return them only after you’re feeling well. Remove the affected parts correctly to prevent cross-contamination.

There is the option to burn the leaves and treat them using fungicides first before burying them far from the garden. Clean up the tools you’ve employed.

To treat fungal illnesses. These are the fungalicides that I suggest:

Leach Off Excess Fertilizers

In the event that brown patches were result of the use of too much fertilizer, you can apply water to remove the salts from the soil. The salts are water-soluble, so it’s not too difficult.

Add a large amount of water over the dirt until it runs out of the container. It is possible to repeat this process multiple times. Make sure that the water is completely drained from the pot to prevent root rot.

Moderate Your Water Application

If the issue is water the issue is water, and that you can control. The monstera that is overwatered should be allowed to dry out initially by exposure to moderate sunlight. This will help the water evaporate more quickly. Repot the plant as needed.

The monstera that is under water should receive sufficient water as soon as the leaves begin to appear bright and full of life. Drip irrigation is essential to ensure that the water is reaching the soil’s bottom.

How To Prevent Brown Spots on Monstera Leaves?

Being a living thing plant, the various stresses that plant tissues experience can influence the way they live. The stress can be natural caused or not.

To prevent brown spots from ruining the leaves of the monstera plant it is essential to prevent or reduce the stress.

Stress reduction leads to healthier plants. Therefore, here are some preventive measures to prevent the appearance of brown marks on your monstera leaves.

Give Sufficient Indirect Light

It’s an indoor plant , so it is thriving in a similar environment. Don’t allow the monstera exposure to sunlight direct. If you do ensure that it isn’t left out for too for too long.

The plant is able to use indirect light to produce photosynthesis, so it’s not a good idea to expose the plants to extreme conditions outdoors. This will only stress the plant.

Prepare for Hot Days and Cold Days

If you own an air conditioner that you turn on during hot days and your home will gain from this.

The cooler temperatures will stop the leaves from developing brown spots due to heat stress.

Insulation must be prepared and ready for the winter months. Locating a safe place is another way to keep the monster from getting cold places.

Always Be on the Lookout for Pests

Do not take any insect lightly. They usually operate in a subtle manner and can grow rapidly in only one day. In a matter of days they could have infected your leaves extensively.

If you notice foreign organisms circling your garden, eliminate it. Certain insects are easily removed simply by spraying water directly on them.

Other species can be removed manually by using your fingers. Make sure to kill them and eliminate them as soon as you can.

Cut Off Infected Leaves As Soon as Possible

This is particularly relevant when the reason for brown spots is caused by insects or diseases.

The removal of infected leaves can help reduce the spread of disease. Do not worry, your monstera will certainly develop new ones.

It is better to rid yourself of infected areas immediately rather instead of exposing the entire plant to the risk of a more serious disease.

Regularly Water Your Monstera

Monstera is a large indoor plant, so it will require more water. It is recommended to water the plant 2 or three times per week and until it is at least 50 % to 70% dry. It all is dependent on the time of year.

Make sure the water is completely drained. Make use of a hose whenever possible to ensure that the pot is well-watered. Sprinkle water all over the pot to ensure an even amount of moisture to the soil.

Always start with a healthy Soil

If you are potting, select an unsterilized soil to be sure that pathogens have been eliminated. This reduces the chance of spreading diseases to your peta. The pathogens can remain in the soil for long periods of time.

A soil that is well-amended and high in organic matter can ensure that the plant is healthy and strong. The nutrients that are available in adequate quantities will reduce the need for fertilizer. The slow-release fertilizers are also favored.

Use Clean Water

It’s easy to transfer bacteria and fungi through the water. If the water you’re using is not clean, it’s feasible to accidentally transfer harmful organisms to your plants and cause further damage.

Tap water is sufficient, but If you are able to collect rainwater, it’s more beneficial. Rainwater isn’t contaminated by chemical and other treatments, so the plants are enthralled by them.

The plants that are outside, after being soaked with rainwater instantly appear vibrant and attractive.

Avoid Excessive Moisture

Misting can be beneficial to plants in hot weather, but not when the relative humidity is high. A humid environment is a friend to pathogens. They have the opportunity to grow.

Let excess moisture evaporate from plants by adding water in the early morning, and not at night. This way, you have enough time for the water to evaporate throughout the day.

Can You Maintain Healthy Monstera Leaves?

The care for monstera is a bit more difficult because the indoor plant is usually massive. The sight of brown spots on its leaves is sure to cause anxiety. There is a chance that you are unsure about whether you are able to make your monster a success.

However, with the right knowledge and comprehension of the above factors you’ll be able to figure out the best way to handle them.

The aim is creating a positive environment for plants to thrive in. Reduce stress, and your plant will succeed. Are you able to do it?



Went from a bad gardener to a half-decent one over 10+ years. Super happy to share my tips and tricks with you :)