Why Does My Monstera Have Brown Spots? Causes And Solution

Monstera Deliciosa or the Swiss Cheese Plant is widely known for its elegant beauty and iconic looks. We keep the plant in our house for various purposes, such as for bringing natural green into our room, or for beautifying our spaces and even for air purification.

Like any other indoor plant, Monstera Deliciosa is also prone to some common issues. Although caring for a Monstera plant is not too difficult, you may encounter some unwanted issues, and the brown spots problem on the leaves is one of them. These spots are not natural, and they don’t just come out at random. Brown spot on the leaves is an issue and various factors can be responsible for this.

TL; DR

Overwatering, fungal infection and poorly draining soil are some of the common reasons why does your Monstera have brown spots on its leaves. However, there are several other reasons too that can cause such issues in your favourite plant and we will discuss them in detail. We will focus on each factor and recommend methods to get rid of them and make your little friend healthy and shiny again.

Causes Of Brown Spots On Monstera Leaves

As a Monstera lover, you might have tried to give the best care possible to the plant. But, issues like brown spots, curling leaves, dying leaves, etc. can emerge due to some mistakes and lack of knowledge. However, you can identify the causes of most issues by inspecting the plant carefully on your own, and the best part is that an issue like brown spots can be addressed easily. Here are some major reasons behind the brown spot problem on Monstera leaves.

1. Overwatering: 

Overwatering is one of the major reasons behind the brown spot problem on Monstera leaves. Remember, overwatering can kill any houseplant and your favourite Monstera Deliciosa is no exception. Indoor plants like Monstera come with aerial roots that require mild moisture to survive.

Therefore, your Monstera plant is not going to tolerate overwatering. Waterlogged soil can cause suffocation and subsequently root rot. If roots are getting rotten inside due to soggy soil, your plant’s distress will be visible.

Containers with ineffective drainage holes can also cause suffocation of roots. Poor draining soil might also be the culprit. If the roots of your Monstera plant are plunged into the water for a long time, root damage is inevitable.

Also Read Why Is My Monstera Plant Dripping Water? 

2. Underwatering:

Even though overwatering can cause root damage, you cannot stop feeding your plant. Underwatering is also a key reason behind the brown spot problem. If you reduce watering drastically, you will leave the plant dehydrated that subsequently resulting in brown spots.

Overwatering is a menace. But, at the same time, you have to consider the fact that Monstera Deliciosa is a tropical plant and a tropical rainforest is its natural home. Hence, you need to provide it with adequate humidity and moisture to help it survive. To keep your Monstera plant happy and healthy, make sure you are watering it carefully and avoid underwatering.

3. Over-Fertilizing:

Fertilization often helps tropical plants like Monstera Deliciosa thrive quickly and looked great. However, here the problem is that too much fertilization is not good for your houseplant. Thinking the plant will grow rapidly, we are often tempted to give more fertilizer.

Such practice is not recommended, as this can even kill the plant. Brown margins, leaf tips and spots are some of the problems that can be caused by over-fertilizing. Here, the risk is that over-fertilization causes fertilizer build-up in the soil.

Monstera’s roots are the soft victim of excessive fertilizer build-up and this is how you can put the life of your beloved plant at risk. Remember, salt available in fertilizers take moisture away from the roots and makes them dry. Hence, be aware of the over-fertilizing factor and fertilize your plant only when it needs.

4. Pests:

Pests can turn out to be the real culprit behind the brown spot problem on your Monstera’s leaves. Houseplants like Monstera Deliciosa are vulnerable to various types of pests like spider mites, scale insects, whiteflies, aphids, etc. Infestation caused by any of these pests can have a deadly impact on your Monstera’s overall health.

If you fail to identify pest infestation on time, it can cause irreparable damage to your plant. Some pests are hard to find and you need to be a little bit careful with them. Finding pests like spider mites can be difficult and you have to look for some signs like thin webs, brown spots on the leaves, curling foliage, etc. On the other hand, if your Monstera plant is suffering from issues like leaf drop and brown or white spots on the leaves, you can hold scale inspects responsible for this.

5. Diseases:

Monstera Deliciosa plants are also vulnerable to fungal and bacterial infection. If you find a single brown spot on a leaf, you can consider it a sign of fungal infection. The number of the spot might gradually increase over time. If you ignore the sign for a long time, the spot can turn out to be large and might turn the entire leaf brown.

If it is a bacterial infection, the number of brown spots will be fewer and the leaves might look wet. Brown spots can be caused by both fungal and bacterial infections and they require immediate treatment.

6. Temperature Fluctuation: 

A sudden drop or rise in the room temperature can also affect the overall health of your Monstera plant. If your houseplant is exposed to extreme hot or cold temperatures, brown spots are expected. If you place the plant close to a radiator, heating or cooling vent, the plant can react to this.

Sudden temperature changes can cause temperature stress in your Monstera plant. Temperatures stress affects physiological processes like photosynthesis and damages the overall health of the plant in many ways. Brown spots on the leaves can be a sign of temperature stress and you need to be careful about this.

7. Excessive Light: 

Considering Monstera Deliciosa a tropical plant, plant parents often place the plant under direct sunlight. Here, you must know that even though Monstera comes from a hot and humid environment, the plant grows under the shades of larger and taller trees. Therefore, they cannot access direct sunlight.

If you place the plant under direct sunlight, excessive heat can burn its leaves and eventually cause brown spots. Remember, indoor plants like Monstera Deliciosa can thrive under indirect lights so there is no need to expose them to direct sunlight or unfavourable outdoor conditions.

Related: How Much Light Does A Monstera Plant Need? 

Different Types Of Brown Spots On Monstera Leaves And Ways To Identify Them

The leaves of the Monstera Deliciosa plant can lose their shine for many reasons. Apart from the reasons we have mentioned above, leaves of Monstera often develop stains due to some natural processes like ageing.

Hence, finding the right brown spots can be a little bit difficult especially when someone doing it for the very first time. Here are some methods to identify the brown spots you need to be worried about.

Before you think about the solution, you need to know how they look. This will help you to identify signs of problems. In general, the colour of the spots can be dark brown or black, but sometimes they might appear a little bit reddish with a yellow circle.

While most spots are formed in irregular shapes, some will appear in ring shapes. The size of the spot can be both large and small. It starts with the small and if ignored for a long time, the size of the spots enlarges gradually. Leaves often look necrotic and may start falling off the plant.

Let us talk about the portion of the plant you need to focus on to identify brown spots. When inspecting the plant, you should focus on heavily shaded areas like the lower canopy. These areas are very vulnerable to forming brown spots. Brown spots can be found across both sides of a leaf. Hence, never forget to check both portions of the leaves before you opt for any solution.

How To Fix Brown Spot Problem On Your Monstera’s Leaves? 

Tropical plants like Monstera Deliciosa are most popular for their lavish green leaves. Any stain on the leaves can affect their overall look and as a plant parent, you will not tolerate this.

Factors that cause brown spots on the leaves can be addressed and you do not have to be an expert for this. Here we will discuss some effective methods to fix brown spots on your favourite Monstera’s leaves.

1. Be Careful When Watering: 

As we have mentioned before that both over and underwatering can damage the overall health of the plant and may lead to brown spots problem, you should be careful about water application. If you think that you have overwatered the plant, allow it to dry off the water.

You can put the plant under moderate sunlight so that the water gets evaporated quickly. Also, if the water draining holes on the pot is not good enough, change the pot immediately.

You can also inspect the roots by gently lifting the plant out of the pot. If you find the roots mushy, black or brown, they are rotten. It is better to cut off the affected roots keeping the healthy roots untouched. Once it is done, wash the roots and repot the plant again.

Likewise, you have to be aware of underwater issues. Monstera deliciosa plants require enough water until their leaves appear to be full and vibrant. As a plant parent, you need to understand how frequently your plant requires a drink. Give more water on warm and dry days than in cooler weather. Also, if your Monstera plant is rootbound, it will require a larger container to hold the water.

2. Check Fertilization: 

If over-fertilization is the real culprit behind brown spots on the Monstera’s leaves, you need to flush out the excess salts from the soil. Fertilizer adds various types of minerals including salts to the soil. When the presence of salts in the soil increases, the roots suffer a lot. Hence, you have to wash out the salt first to help your plant fight root rot.

You have to abstain from overfeeding your plant, as this can kill your plant anytime soon. Sometimes, your Monstera plant requires added nutrients to thrive. But, over-fertilization can hurt the plant in many ways.

You can also use water to drain out the excess salts from the soil. But, the water you have applied to the soil should drain off completely to prevent root rot.

3. Remove Pests Immediately:

If pests are causing the brown spots on your Monstera, you need to take immediate measures to save your plant from those killers. First of all, separate the infected plant from other plants to keep healthy plants safe.

If you do not want to use any pesticides, you can give a thorough wash using a hose or shower gun to remove the pests from leaves and the other parts of the plant.

You can also opt for a chemical-free organic option to eliminate the pests. Horticultural oil can be used to eliminate scale insects, spider mites, etc. For the best outcome, prepare a solution of horticultural oil, water and liquid soap. You can apply the solution directly to the affected areas. 

If you have brought a new plant home, it is better to start with fresh and healthy soil. Go for sterilized soil for the plant to make sure the soil is free of fungi, bacteria or other pathogens. This will minimize the possibility of infestations. Remember, pathogens can live and breed even in fertilised soil for a long period.

4. Isolate the Plant Eliminate Fungi and Bacteria: 

Air and water-borne diseases can also cause brown spots on the leaves of your Monstera plant. Your plant can catch fungi, bacteria and other harmful pathogens from air or water. If the environment is suitable for fungi and bacteria, infections can spread out rapidly.

However, you can address the problem by taking a few measures. Once you identify the problem, take action immediately and prevent infections from spreading. First of all, separate the infected Monstera from other healthy plants. Take it to a well-lit area with the right moisture level.

To save the entire plant from infection, you need to remove the infected leaves by cutting them off. To eliminate fungi and bacteria from the plant, you can opt for organic solutions. Prepare a baking soda solution with other ingredients like vegetable oil and liquid soap.

Baking soda can burn some leaves, hence make sure the percentage of baking soda in the solution is nominal. The Organic solution will restrict the spores from spreading.

5. Keep the Plant Away from Exposure to Extreme Temperature Fluctuation: 

Extreme temperature fluctuation can cause brown spots on the leaves of the Monstera Deliciosa plant. Once the reason is identified, you need to take steps to avoid exposure to extreme temperatures. Keep the plant away from the room heater or fireplace. Extreme heat and cold can also come through the window; hence, placing the plant near an open window will not be a good idea.

A sudden rise and drop in temperature can also harm the plant and force it to react negatively. For example, if you suddenly place the plant under the scorching sun in the summer, it will suffer from temperature stress. On the other hand, if you pick the plant from a hot and humid outdoor environment and suddenly place it under your air conditioning system, temperature shock is inevitable.

Plants like Monstera Deliciosa are also not tolerant to sudden changes in location. Sudden location changes can also cause brown spots due to acclimation. Once the plant experiences acclimation, it suffers from stress. If you are relocating to a new place with your plant, help it with extra care.

Also Read: Monstera Aerial Roots: What Are They And What To Do With Them?

6. Give Moderate Light:

Your Monstera plant is not tolerant to excessive light so make sure you are not placing it under direct sunlight. However, keeping the plant in a dark corner or an extremely low light area will also not be a good idea, as low light can also fade the leaves away.

If your Monstera plant has developed brown or black spots on its leaves due to sunburn or excessive outdoor light, place it in a place that brings in a lot of indirect light.

Conclusion 

We all love Monstera Deliciosa for its unique and shiny leaves. They are beautiful and just looking at them makes us happy. As a Monstera lover, you would not like to see any unwanted spot on its leaves. As we have discussed, improper watering, pests, diseases, over-fertilization, temperature fluctuation, etc. often cause the brown spots problem on Monstera leaves. You can follow our tips to save your beloved plant from the problem. If applied properly, the solutions we have mentioned in the article can help your plant to recover and grow new green leaves again. We want to hear from you. Your valuable suggestions often intrigue us. Please share your thoughts with us and help us learn new things.

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