Monstera is a beautiful houseplant. But a few problems can cause the leaves to turn brown, hurting their beauty.
If you notice your Monstera leaves turning brown, the first thing to do is try finding out what might be causing it. Addressing the problem in good time should help you salvage the plant and likely prevent it from dying.
But what causes Monstera leaves to turn brown? This article discusses eleven notorious culprits behind brown spots on Monstera leaves and how to deal with them.
The article also offers expert advice on how to prevent the problem or handle affected plants to avoid spreading the contamination in transmittable cases.
Why is my Monstera Turning Brown?
The problem of Monstera leaves turning brown can be due to overwatering, underwatering, or prolonged exposure to direct sunlight. Other factors that can cause your Monstera to develop brown spots include disease, low humidity, inadequate nutrients in the soil, and prolonged exposure to a cold draft.
Reasons for Monstera Leaves Turning Brown
Overall, Monstera leaves can develop brown spots due to suboptimal growth conditions or pests and disease attacks.
However, the plant can also normally shed some of its lower leaves in the course of its aging process. For these cases, you won’t need to do anything as the brown leaves will be falling as a natural process.
The important thing is to understand the difference and know if the brown leaves are signaling an underlying problem or not.
Here are the common problems likely to make a brown discoloration sneak up on your Monstera’s leaves.
1. Pests or disease attack
If you see your Monstera leaves turning brown with yellow rings or halos around the brown spots, the problem could be related to a bug attack.
Household pests like mealybugs, spiders, scales, gnats, and aphids can wreak havoc on your Monstera. These creatures can suck moisture from the plant’s leaves, causing dehydration.
You can spot these bugs on the underside of the plant leaf when you look closely at an affected leaf.
Fungal plant pathogens like Spilocaea oleaginea are common culprits on Monstera plants. These fungi are sometimes called peacock eyes because they create eye-like spots on the leaf.
Monstera leaves could also turn brown due to a group of related fungal diseases called Anthracnose. If these attacks are not addressed in time, the plant leaves will turn yellow and then brown. After that, the leaves will fall off, and the plant could die eventually.
A disease-stricken Monstera houseplant will typically show the following symptoms:
- A large number of brown spots with yellow rings around them
- Small brown spots on the leaves that increase in number
- Visible traces of fungal rust or mold appear on the leaves
- Part of the Monstera leaf turns brown before the leaf dies off.
Fungal and pest attacks usually occur as a result of wet foliage. Leaving your Monstera’s leaves wet for prolonged periods will likely invite fungi.
Poor air circulation is another likely cause of pests and disease in these houseplants. Similarly, your plant may get fungal rust and pest infestation if its leaves do not get adequate light.
Avoid letting your Monstera deliciosa’s leaves remain wet for too long, as this encourages the growth of fungi.
Keep your Monstera plant in a well-ventilated area where proper air circulation helps ward off fungi and prevents their growth.
Also, consider installing a humidifier to boost the humidity in the area where your Monstera is growing. Do not mist the plant instead, as this will encourage fungi growth.
Even more importantly, ensure you conduct routine checks for pests and diseases to catch any infections before they cause any serious harm to the plant.
Checking the leaves thoroughly, especially during cleaning or watering sessions, can help you notice any potential problems early. That way, you can address them before they damage your plant leaves.
The best way to deal with disease-affected Monstera leaves is to get rid of them as soon as possible carefully. And avoid misting your plant for the next few days.
You also need to spray the affected plant leaves with fungicide.
To further understand the prevention and treatment of bugs, check out our article on “do indoor plants always attract bugs.”
While your plants require water for their survival, watering your houseplant too frequently will keep the roots constantly wet. This is detrimental to the plant’s health, and should therefore know how often to water your monstera plant.
Monstera plants, like most houseplants, do not appreciate sitting in wet soil. Their roots need to breathe after taking up the required amount of water from the soil to remain healthy. This can only happen when you allow the soil to dry before adding water.
However, some plant owners water their plants too frequently or keep their plants in pots with poor drainage.
This problem is common because many people find it challenging to determine the right amount of water for their plants.
Eventually, the plant spends extended durations in soggy soil, leading to root rot. Rotten roots are unable to take up water and nutrients appropriately, depriving the leaves of these essential elements.
The plant’s leaves will turn yellow and eventually become brown due to dehydration. If the root rot becomes severe, your plant may die.
You can tell that your plant has root rot if it shows the following symptoms:
- Leaves turn partially yellow or brown, especially those at the lower parts of the plant.
- The soil in your plant’s container appears noticeably soggy.
- The Monstera’s roots produce a foul smell and are noticeably mushy.
- Chlorosis occurs on the leaves.
- The plant stops growing or exhibits retarded growth.
- Dark brown spots appear on the leaves.
The first thing you can do to avoid these pitfalls is to avoid following a fixed schedule in watering your Monstera. Instead, always check to ensure the top layer of the soil in your plant’s pot is dry before adding water.
Ideally, about two inches of the topsoil needs to be dry when you water your plant. This often means the soil is no longer soggy underneath.
If you notice the soil stays wet for too long, consider repotting the plant to the right-sized container. If the pot is too small, it may restrict the plant’s roots and affect its ability to take up water.
This problem may also occur if the container is too large that the roots do not reach all the water.
- Carefully prune away the affected brown leaves.
- Remove the plant roots from the pot and inspect them for damage.
- Clean and wash the dirt off the roots if they are rotting.
- Remove all the rotten tissue with a sharp, sterile instrument.
- Use a hydrogen peroxide solution to clean the wounded roots. The solution should consist of one part hydrogen peroxide and ten part water.
- Once done, put the treated Monstera plant in a dry, dark area to dry for several hours.
- After it has dried, repot it in a container with enough drainage holes and sterile, dry soil.
- Leave the soil dry for 7 to 10 days.
- Water the plant after 7 to 10 days have elapsed.
3. Exposure to too much direct sunlight
Monstera plants generally prefer bright, indirect sunlight. Subjecting them to lots of direct sunlight naturally affects their health and potentially burns their leaves.
Tropical climates involve these plants growing under canopies that filter the light, preventing direct sun exposure. These are the same conditions they want to be replicated when you grow them as houseplants.
So you can always put the plant near a window and use sheer curtains to create a soft and bright outdoorsy feeling around the plant. This will allow it all the light it needs.
If your plant’s leaves have turned brown because of sitting under direct sunlight for a long, you may not recover the scorched leaves.
Sunburnt Monstera leaves will have the following symptoms:
- The leaves have large brown spots on their surfaces.
- A mix of yellow and brown areas appears on the leaf, and it becomes crispy and dies off.
How to deal with the sunburnt leaves
- Cut away any badly damaged leaves.
- If the plant is near a south-facing window, move it to a west- or east-facing window.
- Consider moving it some distance from the window if the room is a southern one, allowing about 5 feet between the plant and the south-facing window.
- You could also cover the window with sheer curtains that afford the privacy you need while letting in bright, filtered light.
4. Low humidity
As already mentioned, Monstera is a tropical plant that thrives under high-humidity conditions. Ideally, your Monstera should do best in humidity above 40 percent.
This is because the plant is native to places with humid climates. Their large leaves have big surface areas that make them lose water fast through transpiration if the air around the Monstera has little moisture.
You can tell that low humidity is taking a toll on your houseplant if the leaf margins are getting brown and the plant is drooping.
If this continues, more sections of the leaves will turn brown, which might eventually kill the plant.
How to address the problem
You can increase the indoor humidity around your Monstera plant and keep it above average with these techniques:
- Put some pebbles in a tray and fill it with water to about half the level of the pebbles, then place the pot over the pebbles. Ensure the pot does not touch the water.
- Mist the plant’s leaves every few days with clean water, allowing the leaves to dry each time.
- Put the Monstera plant in your bathroom for approximately 5 minutes with the shower on hot.
- Use a humidifier to increase the indoor humidity around your plant.
Once you have put measures in place to ensure your Monstera plant has the desired humidity, you also want to avoid putting it near a radiator or air conditioning that might suck the moisture from it or dry the air around the plant.
You can also use a hygrometer to constantly check the humidity levels around the plant to ensure they don’t dip too low for the Monstera’s liking.
Regularly monitoring the humidity around the plant can be an excellent way to prevent the leaves from getting brown due to low humidity.
5. Unfavorable water quality
The quality of water used on houseplants can directly affect their nutrient uptake capabilities.
If the water has low pH or is too acidic, it will transfer the acidity to the potting material. This, in turn, interferes with the growth of the plant roots by increasing or decreasing the solubility of micronutrients. This affects their availability for the plant.
This increased soil acidity can also lead to the precipitation of minerals like iron, making them unavailable for the plant.
Too high water pH is not favorable either. It increases the soil’s alkalinity, reducing the solubility of micronutrients like iron.
When these essential nutrients are less soluble, they become unavailable for uptake by your Monstera plant roots.
Since plants can only take up nutrients when dissolved in the soil, the precipitation of nutrients will induce deficiency. The induced iron and other micronutrients deficiency can result in chlorosis noticeable in the leaves.
What causes bad water quality?
The most common culprit in unfavorable water quality is fluoride, a naturally occurring mineral that can easily be present in water at undesirable levels.
Water can also be contaminated by arsenic and nitrate or emerging pollutants like pesticides and pharmaceuticals.
All of these affect the water quality, making it toxic to your houseplant.
Symptoms of unfavorable water quality
Plants receiving bad water or experiencing fluoride toxicity will typically have brown leaf tips.
You can deal with the brown tips resulting from a bad water problem by buying a fluoride test kit and using it to test the quality of your tap water.
If the fluoride levels in the tap water are high, consider using distilled water instead. You can also water your Monstera plants with rainwater instead of tap water to preserve them.
While Monstera and other houseplants do not enjoy sitting in soggy potting mix, their roots should not dry too much either. So you must always find the right balance in your watering schedule.
However, this can be understandably challenging, and plant owners sometimes fall behind in their watering schedules. When this happens, the plant ends up with too dry soil around its roots.
Symptoms of dry soil
- Monstera leaves start turning brown at the tips.
- The leaf plate becomes deformed.
- The leaves may shrivel up over time.
- The potting mix becomes absolutely dry.
These symptoms occur due to the plant’s inability to obtain nutrients and water from the dry soil.
What to do:
- Start by removing the damaged leaves.
- Water your Monstera slowly but deeply. This approach helps ensure no dry patches remain in the soil. Stop watering when the water starts flowing out of the drainage holes.
- Follow a watering routine, ensuring you add water as soon as the top layer of the soil has dried.
7. Lack of sufficient nutrients
Dry soil, rotten roots, and precipitated nutrients due to high or low soil pH often affect the uptake of nutrients from the soil. However, the soil itself can lack some of these essential nutrients that the plant requires.
When essential nutrients are missing, symptoms of nutrient deficiency will occur. Common among these symptoms include leaf discoloration and noticeable stunted growth.
What to do
The best solution to a nutrient deficiency problem is to apply fertilizer with a good balance of phosphorus, potassium, and nitrogen.
You can choose pellets or liquid fertilizer; either form should help improve the soil quality.
If you go for solid fertilizer, you may want to add it during watering to let the soil incorporate it more effectively.
8. Temperature fluctuations—prolonged exposure to a cold draft
Monstera plants are naturally accustomed to tropical climates, which are relatively warm. As such, any significant dip in mercury can affect the plant’s health and damage the leaves.
Still, even though the plant prefers warm weather, the temperatures should not be too high. Prolonged stay under temperatures above 100 degrees Fahrenheit will damage the plant and its leaves.
Too low or too high temperatures will make the Monstera leaves turn brown.
Indoors, putting your Monstera plant too close to an AC or being exposed to a cold draft in the room will cause brown spots to appear on the leaves.
If the exposure goes on for a long time, it will severely damage the leaves, and they will die off.
What to do
- Carefully cut away any leaves that have sustained more than 50 percent tissue damage.
- Relocate the plant to a room with temperatures between 65 and 90 degrees Fahrenheit.
- Do not put the plant anywhere near an air conditioner or refrigerator.
9. Transplanting shock
Your Monstera, like any plant, takes time to adjust to its new growth environment after repotting it.
Even if you water the plant properly, you may notice the leaves turning brown after changing the plant’s potting mix or transferring it into a new pot.
This typically happens due to damage that the roots sustain in the process or just the stress associated with the transplantation process.
Your Monstera roots will need some time to recover their rhythm and restart the proper nutrient uptake.
What to do about the issue
- Chop away any severely damaged foliage.
- Keep the plant away from windows to get maximum shade.
- Return the plant next to a window after a month, and do not fertilize it.
- Water the plant as soon as the top two to three inches of the soil in the pot have dried.
10. Incorrect Potting Mix
Monstera prefers loose soil rich in humus and organic matter. If your Monstera has new, unfurled leaves turning brown or black, improper soil moisture may be responsible.
The wrong potting mix lacks the desired texture and nutrients that your Monstera requires to thrive.
As a result, it may retain water for too long, leading to root rot. Or it may deprive the plant of essential nutrients necessary for its growth.
The soil may also lack the air pockets the roots require to breathe. Either you kept the potting soil wet for too long, or you let the soil dry out completely.
The best solution for a bad potting mix is to change the soil. Replace it with the right potting mix, then water the plant and allow it to grow and thrive.
11. Poor Soil Drainage
Poor soil drainage occurs when the drainage holes are too small, or the soil is too fine. As already mentioned, Monstera likes loose soil with decomposing organic matter.
If the soil has a fine texture, it will retain water for too long. Staying in soggy soil for extended periods can lead to root rot, affecting the plant’s ability to absorb water and take up nutrients from the soil.
With its nutrient and water uptake inhibited, the Monstera plant leaves will start wilting before turning brown and eventually dying.
What to do
When the soil has poor drainage, you can add peat moss to loosen it up or replace it with a potting mix with the right texture.
Why are my Variegated Monstera Leaves Turning Brown?
Your variegated Monstera leaves can turn brown due to a salt buildup in the water or a lack of light. Variegated Monstera plants require a lot of light to tap into the sun’s energy and synthesize food. If the light is minimal, the plant may not get enough energy, and the leaves may turn brown.
Should I cut brown leaves off Monstera?
Yes, you should remove brown leaves from your Monstera plant, as they will typically not recover. Cutting the damaged leaves can also help protect the rest of the Monstera plant, especially if the damage on the leaves is due to pests and disease attacks.
How to cut brown leaves off Monstera
Removing damaged leaves from your Monstera plant requires utmost care if the brown leaves are due to disease or fungal infection. Care is necessary to avoid contaminating the rest of the plant.
So, follow these strict guidelines to do it correctly:
- Cut the leaves at the stem with a sharp, sterilized blade.
- Take care not to damage the Monstera’s main stem, where a new set of leaves will form.
- If the damage is not disease-related, cut only the part of the damaged leaf, leaving the healthy sections.
- Clean your instrument with rubbing alcohol before and after using it to cut fungi- or bacteria-infected leaves.
Why does my Monstera have brown spots?
If you notice dark brown spots on the leaves of your Monstera plant, it may be getting too much water. Overwatering usually leads to the soil staying wet for too long, causing root rot. This is what causes the brown spots on the leaves.
Why is new Monstera leaves turning brown?
New Monstera leaves may turn light brown due to underwatering. So, consider adding water to the pot more often, preferably as soon as the top layer of the soil appears dry. You can also trim the dead, brown crispy edges of the leaves to leave only the healthy part to grow.
How do you treat brown edges on Monstera Leaves?
The best way to treat brown edges on Monstera leaves is to trim the leaves in the shape they are likely to grow. The idea is to remove the dead leaf sections and allow the healthy parts to grow.
Read also: Why Is My Chinese Evergreen Turning Yellow?
Monstera Leaves Turning Brown: Final Thoughts
While brown spots can significantly spoil the beauty of your Monstera leaves, the problem is usually easy to fix with a few simple adjustments to the plant’s care routine.
Whether you have monstera leaves turning brown due to improper care routine or disease, this article provides the recommended methods of dealing with the problem and restoring your plant’s health.
We hope the guidelines in this write-up help you fix the problem with your Monstera and prevent the leaves from turning brown in the future.
Let us know your thoughts in the comments.