Philodendron collectors like me may have noticed ugly black spots on the leaves of their Philodendrons. This situation can be disappointing as being Philodendron lovers, these plants are like our kids. These spots can make the beautiful, lush green leaves look ugly and damaged.
There can be several causes that may led to those spots. It is a quite common problem and can be treated if immediate action is taken.
So, in this post, I will talk more about the reasons for those ugly black spots on the Philodendron leaves and share some effective and useful remedies to treat them. Find out different ways to prevent black spots from the leaves of your beloved plant and keep them healthy and vibrant.
What Are the Causes of Black Spots on Philodendron Leaves?
There can be several reasons behind the occurrence of the black spots. So, identifying the exact cause can only help to treat and prevent it. Here, are some of the causes you need to check out thoroughly.
Diseases Caused by Bacteria
Black spots can be caused due to bacterial diseases. Bacterial diseases mostly occur due to excess moisture which may lead to those unsightly spots on the leaves of the Philodendron. Bacterial Light and Bacterial Leaf Spot are two of the most common bacterial diseases that can cause black spots.
Bacterial Leaf Spot
Overwatered plants have soggy soil which may lead to bacterial leaf spots. These leaf spots grow and thrive in wet and warm conditions. So, excess wet soil can help them to grow and survive fast.
Leaves of the plants affected by bacterial leaf spots have signs like transparent patches along the edges of leaves, that get transformed into brown lesions and surrounded by tan or yellow halos. These spots do not have any uniform pattern or size and appear randomly.
Bacterial Light
Water logging and excess soggy soil can also lead to bacterial blight. This bacterial blight also grows and thrives well in damp conditions and thus causes black spots in the beautiful leaves of a Philodendron. The ugly spots make the tissue die by drying out the leaves.
These bacterial diseases spread very fast so, immediate action needs to be taken to treat and prevent them. Other signs like drooping, curling, or wilting of leaves may occur if the plant is affected by bacterial diseases.
Avoid over-watering the plant and only water after checking the soil’s moisture level. Prune off the affected leaves and use fungicide sprays as soon as possible.
Diseases Caused by Fungi
Most Philodendron leaves are affected by fungal diseases like phytophthora and anthracnose. Unlike most fungi, anthracnose prefers humid and warm conditions and thrives well in these environments. This fungal disease spreads fast during the rainy season or due to watering the plant from above.
Anthracnose
You will notice small circular lesions on the leaves affected by anthracnose. The color of the spots is gray at the beginning but, soon changes to black spots as the tissue dies. Overhead watering and rain can spread the disease rapidly.
Phytophthora
On the other hand, phytophthora affects the roots of the plant rather than the leaves. Inky leaf spots with yellow edges are one of its main symptoms. Some other signs are wilting leaves, root rot, and declined growth rate.
To remove spores, wipe the leaves with a damp cloth. Discard severely infected leaves immediately.
Proper care should be taken to get rid of these fungal diseases. Overwatering should always be avoided. And use fungicide sprays to stop them from spreading.
Root Rotting
Root rot can lead to several diseases including the occurrence of black spots on the leaves of a Philodendron. Overwatering and waterlogging can make the roots rot very fast. A rotten root looks slimy and brown.
As the root does not get enough space to breathe it decays easily. Water logging also stops the plant from absorbing the required nutrients and thus, leads to bacterial and fungal growth.
These diseases also affect the plant’s stem, creating gray splotches that slowly turn black. So, inspecting the roots is very important to prevent the root from getting rot.
If the roots have already rotten then, throw away the current soil and remove the decayed root. Repot the plant into well-draining, aerated fresh soil. If the rot still persists then apply a fungicide drench.
Watering
Over-watering and under-watering can adversely affect the plant’s overall health. Excess soggy soil can cause problems like black spots, browning, and yellowing of leaves in a Philodendron.
Over-watering a Philodendron may lead to waterlogging due to which the root starts getting rotten fast. Too much water can create a suffocating situation by depriving the roots of proper air circulation. Thus, black spots and other problems may arise.
On the other hand, underwatering can make a Philodendron struggle. Without enough water, the plant cannot transport nutrients and thus, start cannibalizing their own tissue. A Philodendron cannot survive without adequate moisture, especially during the summer and spring, as these are the plant’s growing period.
Using distilled or rainwater is best for the plant. You can use tap water after eliminating the chlorine component. Keeping a Philodendron hydrated and using a good potting mix can make the plant thrive well without any spots and blotches. Here is some additional information on watering philodendrons that you might find helpful: Watering Guide: Methods for Healthy Foliage.
Sunburn
As you all know, being a tropical plant Philodendron prefers indirect bright light to grow and survive. Placing this plant in direct scorching sunlight can be very harmful to the plant.
A Philodendron can easily get sunburned if kept in direct sunlight for long. leaves that have sunburn dries out very fast and you may notice brown or black spots around the tips and edges of the leaves.
If your favorite plant has got sunburn then, the first thing you need to do is to move it to a shaded spot. You should prune off the damaged leaves and leave the less affected leaves to encourage new growth. With a little care and the right amount of light, your plant will become as healthy and beautiful as it was previously.
Humidity level
Philodendrons love warm and humid conditions to stay healthy and grow well. These tropical plants are mostly found in the rain forests where they survive in most humid conditions.
Less humidity can cause several problems for the plant. Besides, those ugly black spots you may notice the leaves to be drying out. Unlike excess moisture, too much dryness is also not good for a Philodendron. your plant can become weak and get affected by fungal or bacterial diseases if it is kept in extremely dry conditions.
So, when you are a Philodendron indoors make sure the place around the plant has adequate moisture. Always keep your plant away from vents that produce dry air.
If you are in any dry location then, make sure to use a pebble tray or a humidifier to increase the humidity level around the plant.
Pests
Plants that are infested by pests can have several problems including the occurrence of black spots on their leaves. to prevent leaf loss, you should take immediate action. A Philodendron is often affected by pests like mealy bugs, spider mites, scale insects, and aphids.
These insects make small, bleached, or dark spots on the leaves. If not treated the spots become large and make the leaf fall off easily.
Mealybugs extract sap by spraying honeydew which promotes the growth of black mold. These bugs are white and fluffy.
Spider mites suck out the chlorophyll and puncture the cells. These web-spinning mites can cause discoloration of leaves. Scale insects feed on the underside of the leaves and affix themselves to the stem.
Aphids inject toxins into younger growth when they feed. These tiny pear-shaped insects leave yellow spots on the leaves. Use horticulture oils or insecticidal soap to treat the infestation.
Fertilizer
As you all know a good quality fertilizer provides a boost of nutrients. However, using an excess amount of fertilizer can be harmful to the plant. Using too much fertilizer can make the tip of the leaf burn and black spots can also appear.
As the plant cannot utilize excess minerals and salts, they build up to toxic levels and cause severe damage to the plant. Overusing fertilizer can hamper a Philodendron’s growth and photosynthesis process, causing damage to the outer edges and tissues of a leaf.
So, if you think your plant is over-fertilized and notice the signs of damage then, immediately flush the soil to wash away excess minerals and salts. You also need to take off the damaged leaf to promote new growth. Always go for light feed using diluted fertilizer to keep your Philodendron healthy and safe.
What Should Be Your Treatment Strategies for Black Spots?
Follow the methods shared below as soon as you notice black spots on the leaves of a Philodendron.
| Treatment Strategy | Things to Do |
| Move the Plant Away | Plants kept indoors in houses or offices can get black spots if they are exposed to dry and cold conditions. So, isolate the plant by moving it away from other plants to stop the outbreak. |
| Sterilize the Tools | To stop the spreading of diseases and for new healthy growth of the plant you need to remove the infected foliage. |
| Remove Affected Leaves | To stop the spreading of diseases and for new healthy growth of the plant you need to remove the infected foliage. |
| Use Insecticides | You can use organic bactericide or fungicide to treat an affected plant. Be aware of not damaging the foliage. |
Ways to Treat a Philodendron With Black Spots on Leaves
Here are some treatment methods you should try out to get rid of black spots fast.
| Ways | Details |
| Prune the Plant | The affected stem and leaves should be pruned off to remove the black spots. Make sure you use sterilized tools while pruning. |
| Move the Plant | Placing a Philodendron in direct sunlight can lead to those ugly black spots. So, make sure you relocate the plant in any place with adequate indirect bright light. |
| Use Pest Treatment | Using the right pesticides and insecticidal soaps can help you get rid of bugs that may cause black spots on the leaves of your plant. |
| Fungal Treatment | Using fungicides can be a good idea if your Philodendron is infested by a fungal infection that causes those ugly spots. |
| Right Environment | to prevent fungal and bacterial growth make sure your plant is placed in a location with proper and improved air movement. |
| Repotting | It is better to repot the plant in a new pot with fresh, sterile soil to get rid of root rot and fungal infection. |
How to Prevent the Occurrence of Black Spots on the Leaves of a Philodendron?
Preventing the black spots from affecting your plant is always better than treating them. So, here are some effective ways to prevent the spots on Philodendron leaves.
Watering schedule
As mentioned above, overwatering can be very harmful to your Philodendron. So, following the right watering schedule is very important. Water your plant after checking the moisture level of the soil. Watering the plant early in the morning can be beneficial.
Regular check-up
You should check your plant regularly to find out if it is healthy. Regular inspection can help you to identify any issues with the plant and take immediate action. Always place the plant in indirect bright sunlight and prune it when needed. Always Use sanitized tools.
Humid conditions
Philodendrons love warm and humid conditions. So, make sure the humidity level is high around the place where the plant is kept. To increase the level of humidity you can use a pebble tray or a humidifier.
Repotting
Well-draining, aerated soil is best for a Philodendron. This soil prevents water logging and lets excess water drain out easily creating enough space for the roots to breathe. Repot the plant if it is affected by root rot or other diseases.
Pest control
Wipe off the leaves gently using a soft cloth dipped in soapy water or diluted isopropyl alcohol. This will help you to get rid of the pests easily and save your plant.
Wrapping up
Although black spots on the leaves of a Philodendron are not a very serious condition, not taking immediate action can cause severe damage to the plant. Following the methods and tips shared above you can make your plant healthy and thrive for long.
A little care and attention can make a Philodendron stay beautiful and green forever. A plant with green and fresh leaves not only looks beautiful but, also makes the place look clean and tidy where it is placed.
