Brown Spots On Pothos Leaves? Here’s How To Fix It

Pothos, or Epipremnum aureum, is an easy, beginner-friendly houseplant with an attractive vining habit. You may know this plant as Golden Pothos or Devil’s Ivy. 

As a tropical evergreen, Pothos is grown for its foliage. Most specimens have dark green, heart-shaped leaves. But there are also several varieties out there that offer unique colours and variegation patterns.

While white or yellow variegation is 100% normal, brown spots on Pothos leaves are not. In this article, I’ll help you uncover the source of the discolouration and explain the best steps to take to treat it.

Why Do Pothos Leaves Get Brown Spots

If you notice brown spots on your Pothos, there are a couple of things that could be happening.

The first and most likely explanation is that the spots are areas of leaf tissue that were damaged in some way. Potential causes of the damage include sunburn, chemical exposure, or a lack of moisture.

In some cases, brown spots aren’t part of the actual foliage. They are instead caused by fungal spores built up on the leaf surface. You can sometimes wipe away these spores although doing so won’t treat the infection at its source.

Brown Spots On Pothos Symptoms

When diagnosing the cause of the brown spots on your Pothos, you must first of all take notice of all of the presenting symptoms. This will allow you to narrow down the exact cause. This makes treating and fixing the problem a much simpler and straightforward task.

Pothos Leaves with Brown Spots

The fungus Rhizoctonia solani causes dark, necrotic spots on Pothos leaves. These spots are irregularly shaped and can vary greatly in size. According to the University of Florida, it is often spread via infected plants and potting soil. 

If brown spots appear suddenly and your Pothos is otherwise in good health, they might be the result of chemical damage. To prevent future damage, avoid getting liquid fertilizers, fungicides, and other chemicals on the leaves. 

Isolated brown spots can also occur if your Pothos is placed in harsh sunlight. You’re more likely to see spots on sections of the plant that receive the most direct sun exposure.

Pothos Leaves Turning Yellow With Brown Spots

In my experience, yellow leaves with brown spots are the hardest to diagnose as this can be caused by watering issues. This issue can arise for a number of reasons including overwatering the plant, planting in soil that retains too much water or planting in containers with small or no drainage holes. IF the watering issue is not corrected quickly the likely outcome will be root rot.

Additionally, yellow leaves with brown spots may be a result of a lack of potassium. A simple soil test can be conducted to assess the soil pH and any deficiencies that may be present.

If your Pothos has yellow leaves with brown or black veins, it may be suffering from bacterial wilt. This disease is caused by Ralstonia solanacearum.

Bacterial leaf spot (often caused by Xanthomonas campestris) is another common disease in Pothos. Dark spots surrounded by yellow rings are the most obvious symptom here. Plants infected with bacterial infections should be destroyed and all tools disinfected.

pothos with yellow leaves and dark brown spots

Pothos Leaves With Brown Tips Or Edges

According to Iowa State University, browning that starts along leaf margins is usually caused by moisture issues. Your Pothos may be suffering from low humidity, underwatering, or poor water quality. In some cases, fertilizer burn can also be to blame.

Pothos Leaves Turning Brown and Curling

If your Pothos leaves are brown and curling, there’s a good chance it is chronically underwatered. Double-check the humidity levels around your Pothos as well.

Causes of Brown Spots on Pothos Leaves and How To Fix

When leaves develop brown spots, they will unlikely disappear or fade because the leaf cells and tissue have been damaged permanently. However, as long as you address the cause of the spots, new foliage should emerge green and healthy.

In most cases, brown spots on Pothos leaves can be traced back to the environment in which your plant is grown or the care it is (or is not) receiving. In this section I’ll be looking in more details at the causes of brown spots and explaining everything you need to do to fix it.

Watering Problems

Moisture loss is one of the most common causes of brown spots on Pothos leaves. This can be the result of over or underwatering.

Though it seems counter-intuitive, overwatering a potted plant can trigger the same symptoms as underwatering. Damp soil encourages root rot, which damages the roots and prevents them from taking in moisture. As a result, the plant becomes dehydrated regardless of how much water is in the soil.

Low Humidity

Extremely dry air can also pull moisture out of your Pothos and cause the tips, edges, and previously damaged parts of leaves to turn brown. 

Pothos can survive in average household humidity but will truly thrive in moderate humidity conditions of between 50 and 70%.

Fertilizer Burn

Fertilizer can damage your Pothos in a couple of different ways.

Typical fertilizer burn causes damage to roots and occurs when you apply highly concentrated formulas such as a 20-20-20 NPK or if you fertilize too often. When roots become damaged they are unable to effectively take in moisture and nutrients. Over time, this affects leaves and stems causing discoloration at the base of the plant first.

It’s also possible for brown spots to form on Pothos leaves when liquid fertilizer comes into contact with the foliage. Be sure to only apply fertilizer directly to the soil unless otherwise instructed by the product label.

Regular pothos pruning to remove damaged or discolored leaves with improve the look of your plant. Plus, using a balanced houseplant fertilizer with an NPK of 10-10-10 or less that has been diluted by half in water is the best way to prevent salt build-up in the soil and prevent scorched leaves.

Excess Sun Exposure

Pothos plants are native to tropical regions and are adapted to thrive in bright, indirect light under the canopy of taller plants and trees. If they are exposed to too much direct sunlight, the leaves can become damaged and develop brown or yellow spots on the leaves.

To prevent this problem, place your Pothos in a bright spot that receives indirect sunlight or dappled shade. If your Pothos plant is currently in direct sunlight, move it or use a sheer curtain to filter the sunlight intensity.

Temperature Shock

Extreme heat or cold can shock your Pothos and cause its leaves to turn brown, wilt, and fall off. This is the plant’s natural defence mechanism against inhospitable growing conditions. 

Temperature shock often affects entire leaves. However, you might notice brown spots if the Pothos is exposed to an uneven temperature source.

Keep your Pothos in a location where the temperature can be moderated and will remain constant. Avoid drafty windows, air conditioning vents or radiators.

Bacterial Leaf Spot Disease

Bacterial leaf spot is a common disease that causes brown spots with yellow edges on Pothos leaves. It usually occurs if plants become stressed due to very high levels of humidity or when severe over watering has taken place.

This type of bacterial disease needs to be caught early for the best chances of success and if left untreated, the problem will spread throughout the plant and on to neighboring plants too. 

If you suspect that an infection is causing the brown spots on your Pothos, I recommend isolating the plant and removing and destroying affected leaves immediately. Check soil moisture levels too. If the soil remains constantly damp then I recommend switching to a well-draining soil mix or adding grit or perlite to improve drainage. Additionally make sure that the pot has drainage holes that are not blocked.

Pest Infestation

Mealybugs, aphids, spider mites and scale are the most common culprits when it comes to pest infestations. They all have the potential to cause yellow and brown spots on your Pothos where they have damaged the cell structure by sucking sap from the leaves.

These tiny pests are not always easy to spot so you will need to thoroughly inspect your plant especially on the underside of leaves and at stem junctions or near nodes.

Treat pest infestations by blasting off as much of the infestation as you can with a water hose or shower head. Then, use a damp cloth to brush off any other ‘hangers on’ that are still visible to the naked eye.

It is unlikely that you will have dislodged all of the infestation because they are just too small to see so I recommend dousing a cotton pad with insecticide and wiping any areas of the plant that have been infected. Remember to get into the nooks and crannies of nodes and leaf junctions.

You will need to repeat this process weekly until the infestation has been completely cleared.

Remove and discard the leaves that have been damaged by an infestation. Not only will this help to prevent the spread of the disease to other parts of the plant, it will also improve your plant’s health and chances of survival. 

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Ben's horticultural interest grew when graduating from Hertfordshire University in 1997. Having contributed to numerous publications including Better Homes & Gardens, Garden Design Magazine, and The English Garden. He is also the author of Propagating Houseplants Made Easy.