If you’ve had a Monstera for a while you’ve probably come across those dreaded brown spots. But even if you’re new to looking after a Monstera plant you might still be seeing brown patches on it’s leaves.
I’ve had to nurse many Monsteras back from the brink (and killing a few along the way, let’s be honest). So I’ve seen pretty much every way brown spots can develop.
I know how disappointing it can be to feel like you’re doing something wrong. And so I’m here to help you to both diagnose why your Monstera has brown spots and how to best fix it.
Understanding Your Monstera Plant
The most basic point is that if you don’t give your Monstera what it needs the result will be those frustrating brown spots. Monstera are native to tropical rainforests of Central America. And the rainforests are a lot different to our homes. So because of the environment they grow in they’ve evolved to thrive in specific conditions: bright indirect light, a good amount of moisture and high humidity.
A mistake I made with one of my first Monsteras was putting it in a corner and expecting it to just do its thing. Three weeks later it had brown spots everywhere. What I learned was Monsteras are incredibly resilient but at the same time surprisingly fussy.
The problem is that brown spots can mean about a dozen different things. It could be too much water all the way through to pest infestations. What’s worse, if you leave the problems untreated it won’t just ruin your Monsteras good looks, it can eventually kill it completely.
Most Monstera owners don’t realize that they’re very good at communicating their needs. Those brown spots? That’s your Monstera clearly asking for help in the only way it can. Learning to interpret these signs will not only save your current Monstera but make you better at caring for all your houseplants.
12 Reasons Your Monstera Has Brown Spots
1. Overwatering
The most common killer of Monsteras isn’t neglect but giving them too much water. I nearly drowned my Monstera deliciosa by watering it twice a week during a really humid spell. It ended up with soft, dark brown spots that spread across a lot of the leaves.
Why It Happens:
When the soil is constantly wet it means the roots can’t get oxygen. They start to rot and the plant can’t move any nutrients. So the brown spots you are seeing is your plant drowning from the roots up.
How to Fix It:
- Quickly check the soil moisture – stick your finger 2 inches deep. If it’s wet then hold off with watering.
- Set up a watering routine and only water your Monstera when the top 2 to 3 inches of soil are dry
- If the soil is staying wet for more than a week after watering then you might want to repot it
- Make sure your pot has drainage holes (this is extremely important)
If root rot has set in you might need to take more drastic action. I’ve had to take my Monstera out of its pot, wash off all the soil, trim the black or mushy roots before finally repotting it in fresh soil. It lost a few leaves but survived in the end.
2. Underwatering
As we’ve just seen overwatering is terrible for Monsteras. But at the other end or the spectrum is underwatering, which is just as bad. Underwatered Monsteras develop crispy, brown edges that eventually spread to the whole leaf.
Why It Happens:
Without enough water plant cells begin to die. This starts at the thinnest parts of the leaves, which are the edges and tips.
How to Fix It:
- Give your Monstera a good soak – water it thoroughly until water runs from the drainage holes
- Come up with your own consistent watering schedule
- Use a moisture meter if you’re struggling to judge when is the right time to water
- Don’t cut off brown tips. The damage is already done at this point and the plant has sealed those areas off
A moisture meter has been a godsend to me. They’re really affordable and take all the guesswork out of knowing when to water.
3. Too Much Direct Sunlight
Too much sun can give your Monstera sunburn. And when I say sunburn I mean literally. The direct sunlight will bleach areas of the leaves that then turn brown.
I moved a Monstera of mine next to a south facing window during the winter as I thought it needed more light. Three days later though I found it with sunburned leaves and brown patches.
Why It Happens:
In nature Monstera are protected from very strong sunlight by the canopy above them. So they’re simply not used to and not built for direct sunlight. Which is why if you subject yours to it then it will suffer.
How to Fix It:
- Move your Monstera 3 to 6 feet away from windows with direct sunlight
- Use sheer curtains to filter light
- If the leaves on your Monstera are feeling warm when you touch them then that means they’re getting too much light
- Rotate your plant often so all sides get an even amount of light
Unfortunately sunburned spots don’t heal. But your plant will eventually grow new leaves if you care for it the right way.
4. Low Humidity
Brown and crispy leaves don’t have to be caused by water. The air being too dry is also a big problem.
For example in the past I lived in an apartment that dropped to about 30% humidity in winter. At that time if I don’t do something to help them then my Monstera would develop brown edges.
Why It Happens:
Monsteras are tropical plants used to 60 to 80% humidity. In our homes (especially with heating or AC running) the humidity will often drop below 40%. This results in the leaf edges drying out.
How to Fix It:
- If you have more than one plant then try grouping them together as they will create a microclimate with much better humidity
- Fill a tray with pebbles and water and place your Monstera on top (not touching the water)
- Use a humidifier (probably the most effective solution)
- Don’t put your Monstera near heaters or AC vents
I bought a $30 humidifier that runs for 24 hours on one fill. It’s made a massive different to my tropical plants.
5. Pest Infestation
Small brown spots, especially along veins or under leaves, are a clear sign you’ve got some pests. Spider mites once colonized my Monstera while I was away for a week. It was obvious to see what the cause was as they look like tiny little brown specks and leave a sort of webbing all over the leaves.
Common Culprits:
- Spider mites – look for tiny speckled damage and fine webbing
- Scale – appear as brown bumps that can be scraped off
- Thrips – there will be silvery patches that turn brown
- Mealybugs – leave a residue like cotton and brown damage
How to Fix It:
- Keep your plant away from any others to stop any of the pests spreading
- Spray the plant with water to knock off as many pests as possible
- Treat with insecticidal soap, neem oil, or if you’re really desperate, a systemic insecticide
- Keep going with the treatment every week for at least a month (these nasty bugs are persistent)
Prevention is your best bet. I now inspect new plants thoroughly and quarantine them for two weeks before introducing them too the rest of my plants.
6. Fungal Infection
Circular brown spots with yellow halos are classic signs of a fungal issues. I caused this on one of my Monsteras by spilling some water on it and then not drying it off. Soon after the brown spots with yellow rings appeared.
Why It Happens:
Fungi thrive in moist environments. So anything like water sitting on the leaves, especially when there’s poor air circulation, creates the ideal conditions for fungal growth.
How to Fix It:
- Improve the air circulation around your Monstera
- Avoid getting the leaves wet when watering
- Treat with a copper based fungicide or neem oil
- Remove any heavily infected leaves so they don’t spread to the rest of your plant
7. Fertilizer Burn
Brown spots appearing soon after feeding could be fertilizer burn. When I was going through an overzealous, new plant parent phase, I thought more fertilizer would mean faster growth. That proved to be wrong when my Monstera started getting brown spots along the edges of it’s leaves.
Why It Happens:
Too much fertilizer creates a high concentration of salts in the soil. This can damage roots and result in leaf burn.
How to Fix It:
- Flush the soil thoroughly. That means running water through it for several minutes to wash away any excess fertilizer
- Switch to a gentler organic fertilizer or dilute synthetic fertilizers to half the recommended strength
- Follow a seasonal fertilizing schedule – more in growing season and none in winter
- When in doubt always under fertilize rather than over fertilize
I now use a much gentler organic fertilizer at half strength every 6 to 8 weeks. I do that only during growing season too. Since I’ve switched it up I’ve had no more fertilizer burns.
8. Temperature Stress
Sudden brown patches can appear after a temperature shock. My Monstera developed brown spots after being too close to a drafty window during a cold snap. The temperatures dropped to 55°F at night, which is far too cold for something like a Monstera.
Why It Happens:
Monsteras prefer steady temperatures between 65 to 85°F. Cold drafts, sudden temperature drops, or hot, dry air will stress them.
How to Fix It:
- Keep plants away from drafty windows, doors and HVAC vents
- Don’t place your Monsteras near radiators or heating elements
- If you’re using air conditioning in the summer make sure your plant isn’t in the direct airflow
- Use a thermometer to keep track of the temperature when you keep your Monstera
9. Physical Damage
Not all brown spots are down to how you’re caring for your plant. Sometimes they’re just battle scars. My cat once decided my Monstera was an enemy to be conquered. She had a real go at it and the teats her sharp claws made turned brown along the edges.
Why It Happens:
Bumping into the plant, pets playing with it, rough handling during repotting etc. can all cause little injuries that turn into brown as they heal.
How to Fix It:
- Keep your Monstera in an area that doesn’t have lots of people walking past or around it
- Be gentle when cleaning or moving it
- Keep any pets away. Make barriers if need be
- Accept that some damage is cosmetic only and won’t harm the plant
10. Water Quality
If you feel like you’re doing everything right and caring for your Monstera as best as possible but stop getting brown spots – it could be the water.
And I don’t mean over or under watering. I mean the quality of it.
When I moved to a new apartment my Monstera pretty quickly developed brown spots despite me keeping to the same care routine as before I moved. What it turned out to be was highly chlorinated tap water.
Why It Happens:
Chlorine, fluoride and dissolved minerals in tap water can build up in the soil and cause leaf burn over a long enough period.
How to Fix It:
- Let your tap water sit out overnight before using it (this allows the chlorine to dissipate)
- Collect rainwater for watering if possible
- Switch to using filtered or distilled water
- Flush the soil thoroughly every few months to remove minerals that may have built up
Something I now do is keep a watering can filled and sitting out for at least 24 hours before I use it on my most sensitive plants.
11. Aging
Sometimes brown spots are simply a natural part of getting older. My oldest Monstera often gets yellow leaves that then develop brown spots before they drop off.
Why It Happens:
As Monsteras grow taller they naturally divert energy away from the older and lower leaves. These leaves will eventually die off as part of the plant’s normal life cycle.
How to Fix It:
- If only the oldest, lowest leaves are affected then you have nothing to worry about
- Trim completely brown leaves to keep the plant looking tidy
This is the one situation where any brown spots are actually normal.
12. Bacterial Infection
Wet, dark brown spots that seem to spread and have a nasty smell are probably bacterial. I’ve seen Monstera with what looked like water damage which turned out to be an infection.
Why It Happens:
Bacteria gets into wounds or water soaked tissues and then multiply quickly inside the leaf.
How to Fix It:
- Immediately remove and destroy any affected leaves (don’t compost them)
- Sterilize your cutting tools with rubbing alcohol between cuts
- Keep leaves dry and improve air circulation
- If you have a severe case of infection then use a copper based bactericide
With bacterial infections you have to act fast. You may have to cut away a lot of your plant to save it. But in the long run it’s worth doing so.
Frequently Asked Questions
Should I cut off Monstera leaves with brown spots?
It depends on the extent of damage. For leaves that are more than 50% brown or showing signs of infection, yes, remove them. If the damage is just cosmetic and fairly minor then it’s better to leave them. The plant can still photosynthesize with the green portions. Never remove more than 20% of the plant’s leaves at once.
Can brown spots on Monstera leaves be reversed?
Unfortunately not. Oncr leaf tissue turns brown it won’t turn green again. The plant will seal off damaged areas though. Your goal should be preventing spread and encouraging healthy new growth.
How often should I water my Monstera to prevent brown spots?
There’s no answer to this as every plant is different. Instead water when the top 2 to 3 inches of soil feels dry. This might be weekly in summer and every 10 to 14 days in winter. It could be more or less though. Your pot size, soil mix and home conditions all affect how often you should be watering.
What’s the difference between brown spots from overwatering versus underwatering?
Overwatering typically causes soft, dark brown spots that can appear anywhere on the leaf, often with yellowing around them. Underwatering causes crispy, dry brown areas that are mostly at the leaf edges and tips.
Are coffee grounds good for Monstera plants with brown spots?
While coffee grounds can add nitrogen to the soil they’re not a cure for brown spots. In fact they can make problems worse by encouraging mold to grow. Deal with the underlying cause of the brown spots first before you think about using coffee grounds.
Final Thoughts
Brown spots are unsightly and not a good sign. The good news though is that most Monstera problems can be fixed with the proper diagnosis and having a little patience. Even a severely damaged plant can bounce back once you care for it properly.
Keep observing your Monstera, adjusting how you look after it and learning from how it responds. That relationship – the communication between you and your Monstera – is what makes looking after plants so enjoyable. With time and attention any brown spots will become less frequent and your Monstera will give you it’s hole filled leaves that are so beautiful.