Bacterial Leaf Spot on Monstera Signs

Bacterial Leaf Spot on Monstera Signs Image

Have you ever encountered a devastating combination of yellow or brown spots on your monstera plant?

If so, alas, you have been one of the unfortunate cases to discover that your beloved Monstera has fallen victim to a bacterial leaf spot. While this condition may seem daringly alarming and detrimental at first, don’t fret!

We’re here with an informative guide that will help you regain control over bacterial leaf spot on monstera in no time.
Let’s get started and bring back some lushness into our life.

What Causes Bacterial Leaf Spot Monstera Plants?

If you’ve got an infected plant with leaf spots, blame it on a plant bacteria for causing explicitly serious infections.

Examples of these bacterial species include the following:

  • Pseudomonas
  • Xanthomonas
  • Erwinia

Apparently, the two main culprits responsible for predisposing of bacteria are overwatering and moisture.

This infection, in most cases, affects the household monstera species. A good example is the Monstera Deliciosa or half moon Monstera. Unfortunately, that makes me sad because I love keeping this specific monstera species.

Transfer From Another Plant

Bacteria on a monstera leaf spread from one plant to another rapidly. So, if in any way you’ve put your plants closer to each other, they may move.

The transfer will take place because the bacteria are tiny and are easily carried away by wind and insects.


Another primary cause of these bacterial diseases on monstera leaves is overwatering. It causes the monstera soil to be wet and runny all the time.

Naturally, the soil has poor sunlight and air circulation; therefore, overwatering accelerates the conditions for bacteria on your monster leaves.

Watering your monstera when the soil’s top 3 inches isn’t dry is wrong because you’ll be overwatering the plant.

Check your pot’s drainage and the potting soil so that if either stores water, change it immediately.

Moist and Humid Conditions

High humidity is a fundamental care need for monstera plants.

Combined together with poor circulation and overwatering, your plant may suffer a severe bacteria attack.

Use of Infected Gardening Tools

Infected gardening tools and monstera pots are the biggest culprits in this bacterial infection. Unfortunately, some gardeners forget to clean the tools well, risking the chances of bacteria attack on monster leaves.

Other than cleaning and washing, disinfect the gardening tools properly after use. Practicing this trend saves your plant from carrying bacteria from other plants that could be infected already.

Signs of Monstera Bacterial Leaf Spots

Here are the common signs to look for in monstera leaf to determine bacteria attacks.

Signs of Monstera Bacterial Leaf Spots Image

1. Dark Leaf Spots

Among the symptoms of a bacterial leaf spot, dark spots are the most common. These spots vary in color, size, and shape and appear as the first signs.

They appear as small dark brown or black circles that gradually enlarge to create an irregular discoloration. These spots are surrounded by a yellow halo, adding to the concern of leaf spot diseases.

2. Wilting Leaves

Your plant’s leaves begin to fall or wilt when they are suffering from a bacterial leaf spot.

This wilting can occur in any part of the leaves, from the edges to the center, and eventually leads to entire sections of foliage drying out quickly.

Wilted or dried sections may also become discolored, turning yellow and brown as it progresses.

3. Spots range in size

The spot sizes you’ll see vary dramatically, from very small spots to ones that can grow up to 1.5 centimeters in diameter.

If a large number of leaves have been affected by bacterial leaf spot, the plant may suffer defoliation and become weak.

4. Water-soaked spots

You may notice some water-soaked spots appearing on your monstera leaves, even though such spots typically appear on older leaves. 

The spots enlarge and become brown or black with a sunken center. Eventually, lesions can expand to cover entire leaflets

5. Leaf collapse

Once the bacteria leaf spots spread, the affected monstera leaves collapse.

Soon, you start noticing several affected leaves littering the monstera soil’s top. Ensure you remove the infected leaves immediately. 

6. Dry and papery spots

Older leaf spots may start drying and developing paper-like textures. As the leaves turn dry, they remain dark brown, black, and reddish in color.

7. Discoloration of the leaves’ edges

The leaves’ edges discolor, turning yellow, dark brown, or black. The spots will start small and gradually grow larger until the entire leaf is affected. This discoloration happens immediately after the spots appear on the leaves. 

8. Oozy leaf spots

Some of the spots on the monstera leaves will start oozing sticky bacterial substances. That may or may not happen, but when it does, it will appear on old and new leaf spots.

9. Leaf spots run together

Most spots enlarge the more the plant stays in wet conditions. Then, they merge or run together, forming bigger spots.

10. Unpleasant odor

If you didn’t know, bacterial leaf spots sometimes cause unpleasant smells. So, if your monstera smells unpleasant, it has bacteria.

You’ll notice a musty or rot smell when this bacteria progresses.

11. Curling or Twisting of the Leaves

When the infection spreads over time, the monstera leaves become distorted. That’s a sign that your monstera is trying hard to fight against the bacteria. 

How Do You Treat Bacterial Leaf Spot on Monstera?

To make your work easier, here are a few ways to treat your bacterial leaf spot on Monstera.

1. Reduce watering

Again, overwatering is a common cause of bacterial infections on monstera and the exact cause of fungal infections.

If you notice this bacterial disease on your lovely monstera, reduce excessive watering, making sure you only water when it is necessary.

2. Reduce the humidity level

Check the humidity level in the room where your Monstera is located.

If it is too high, consider investing in a dehumidifier to reduce the risk of bacterial leaf spot. You can also improvise by placing a few fans around the room.

3. Increase airflow

Ensure that there is enough air circulation in your home or greenhouse where you keep your Monstera.

This will help prevent bacteria from settling and multiplying on the leaves of the plant.

4. Prune infected leaves

While it may be possible to wait on the leaves recovery, it would help if you remove and discard the infected leaves.

However, keep in mind that overlying the plant’s prune is wrong. That’s so since removing some or most of the leaves will hurt your monstera.

5. Isolate the plant

Avoid mixing your infected monster with the rest of the healthy plants, or else the bacteria leaf spots will spread.

Don’t also overly touch your monster, and disinfect the pruning shears often after working on your diseased monstera.

6. Apply copper fungicide

Using copper fungicide is an artificial method of controlling bacterial leaf spot on Monstera plants, but it’s popular among the most effective ways.

Copper fungicides work by inhibiting the growth of bacteria and treating fungal infections that cause this issue.

When using copper fungicide, it is important to follow the instructions provided; or else you risk causing damage to your Monstera plant. To properly apply this treatment, spray the affected leaves with a

How to Prevent Bacterial Leaf Spot on Monstera

1. Avoid overwatering

To help you keep your monstera plant healthy and free from bacteria, water it when its soil feels dry.

You can test the monstera soil using your finger about two inches into the soil. If the soil feels damp, redo the test after a day or two. 

2. Properly care for the monstera

Providing your monstera with ideal growing conditions will help keep it healthy and happy.

This action prevents bacterial leaf spot occurrence while at the same time  helping with recovery

Besides, monstera can quickly recover from this bacterial infection. But that’s if only it’s strong and healthy.

3. Don’t overcrowd the plant

Overcrowding can promote the spread of bacterial leaf spot and other diseases. Make sure to keep your Monstera in a pot with plenty of space for air circulation.

If you notice any signs that your plant is becoming overly crowded, such as yellowing leaves or stunted growth, it’s time to give it a larger home.

4. Remove any fallen leaf debris

Leaving leaf debris on the soil’s top can turn into a host for problems and pests.

Apart from encouraging the development of bacterial leaf spots, the debris will add rot and attract insects and other fungal diseases.

What’s the Difference Between Monstera Fungal Infection and Bacterial Leaf Spot?

Fungus or bacteria both cause leaf spots on your monstera plant. Moreover, leaf spots from the two look similar. Then again, distinguishing them might be challenging. 

But, the good news is that spots from the two have similar prevention and treatment measures. It’s somewhat highly challenging to differentiate bacterial and fungal spots on monstera.

It’s so challenging that most plant parents don’t bother if it’s fungal or bacterial. Instead, they jump right into it and start treating the issue. That’s because both bacterial and fungal leaf spots need similar treatment.

Even better, they need similar preventive measures.

1. Appearance of spots

Often, bacterial leaf spots have an extra angular look, unlike fungal leaf spots. But that isn’t a hard-fast rule.

2. Yellow halo around spots

Bacterial leaf spots have yellow halos around them, although some of the spots aren’t a result of bacteria.

3. Soft rot can occur on the leaves

In some cases, bacterial leaf spots may cause soft rot to develop on the leaves. That can happen at the leaf’s tip, then extend upward.

Unfortunately, some fungal pathogens can cause soft rot on the monstera leaves. 


What does bacterial leaf spot look like?

Bacterial leaf spot starts as small dark brown or black spots. These spots may have halos of yellow tissue that surround each spot. In other cases, the leaf’s center may dry up, falling out. It may give the leaf appearance similar to a “shot hole.”

How do you treat a fungal infection in monstera?

To treat a fungal infection in monstera, it is important first to identify the fungal infection. Once you have identified the type of fungal infection, you can use a number of treatments like fungicides. They will kill or inhibit the growth of fungi and other pathogens.

Does bacterial leaf spot spread?

Yes, bacterial leaf spot does spread, but the extent of how much it will depend on the environment and weather conditions. It can start slowly and then gradually spread to other close-by plants, water splashes, rain, and air currents.

Is bacterial leaf spot contagious?

Bacterial leaf spot is highly contagious. Once infected by the bacterial leaf spot pathogen, plants may be susceptible to repeated infections. Water-splashing of leaves, transmission through contaminated pruning tools, the flow of windborne spores between plants and even plant-to-plant contact are some of possible sources of infection.

Can you save a plant from bacterial leaf spot?

Yes, it is possible to save a plant from bacterial leaf spot. First, inspect the affected area for signs of bacteria, such as dark spots on the leaves. If you spot any symptoms, prune off affected parts of the plant and dispose. Then, water your plant less often to prevent the further spread of the disease.


Bacterial leaf spot on monstera is inevitable. Apart from pruning and irrigation, you can clear this bacterial infection using the following:

  • Baking soda
  • Neem oil
  • Bacterial agents

But over and above, preventing the bacteria is the best solution. So please, continuously improve your monstera’s air circulation and moisture needs.

Also, note that your monstera needs a lot of warmth and sunshine. 

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