11 Causes of Brown Pothos Leaves (Tips for Prevention)
Pothoses are gorgeous hanging plants and browning ruins their looks, right? It’s aggravating that this browning can appear as blotches or spots in the leaf centers or at the leaf margins. I once asked myself, “So what is the cause of browning if it is revealed as small spots? Or blotches?”
Generally, browning on pothos leaves can result from overwatering, underwatering, using tap or hard water, overfertilization, too little or too much sunlight, low relative humidity, root rot, bacterial wilt disease, or scale bug infestation.
It is critical to manage the environmental conditions surrounding a pothos plant to avoid having brown spots on them. If you’re wondering what these factors are, you should keep reading!
1. Overwatering
Overwatering pothos will result in browning because too much water in the soil leads to deprivation of oxygen. When oxygen levels are low, there is a difficulty to transport water and nutrients toward the pothos plant.
Browning Location: Leaf margins or as blotches at the center of pothos leaves.
Imagine drinking water non-stop for 24 hours. You’d likely feel uncomfortable. But, that is the point. Just like us, plants also need time and space to breathe.
When plants are overwatered, oxygen finds it difficult to get into the roots. The aftermath? Yellowing and eventual browning.
Continuous exposure to this condition leads to a slow down in the biological process of growth and development in plants. The first symptom is yellowing and a loss of vigor, followed by browning.
Pro Tip: Do not water pothos plants daily, water them only once every week!
2. Underwatering
Because water is required to transfer and power biological processes such as photosynthesis, an excessively dry soil will prevent the pothos plant from growing and will cause the leaves to dry up and turn brown.
Browning Location: Leaf margins or tips of pothos leaves.
Even though pothos can be watered only once a week, letting them dry out for so long—for instance, more than 2 weeks—will also kill them.
Remember that your plants are made up of water, which is why when you pinch them, fluid will come out. So, if you deprive them of water resources, they will turn brown, crisp, and wilt.
Pro Tip: Have a fixed watering schedule. I found it really helpful to put it in my alarm—so maybe this will work for you too!
3. Using Tap Water
Pothos leaves curl up and turn brown due to a lack of biological resources caused by the use of tap water. Tap water contains chlorides and fluorides that can buildup into salts. These salt compounds will then block the roots of the pothos plant and hinder the transfer of oxygen, water, and nutrients.
Browning Location: Leaf margins, tips, or as blotches at the center of pothos leaves.
Before we start discussing this factor, we first need to acknowledge that each area has different qualities of tap water. Thus, it is advised to ask your water provider about the quality of your home water. In the next section, I will reveal how to measure this using a simple apparatus—the TDS meter.
Pro Tip: Use distilled water instead of tap water when watering your pothos plants. This is because the filtration system removes naturally occurring compounds such as salts that cause buildup in the soil.
4. Using Hard Water
The use of hard water causes mineral buildup in the soil of pothos plants which, in turn, cause browning. Hard water contains additional calcium and magnesium, in large amounts that inhibit the passage of water and air in the roots.
Browning Location: Leaf margins, tips, or blotches at the center of pothos leaves.
To know the hardness of your water, you can use the total dissolved solids (TDS) as an indicator.
Pro Tip: Determine the TDS of your water using a TDS meter. The general rule is that the higher the TDS, the higher the calcium and magnesium content of your water. TDS should be between 50 and 150.
A low-cost TDS meter like the one shown below will work fine for this purpose.
If the hardness of your water is very high, do not use that in watering your pothos! You can use distilled water instead!
However…
Pro Tip: If you do want to change the hardness of the water in your entire home water system, attaching a water softener like the one below is a quick way to lower the calcium and magnesium levels in your water.
Explore different water types in this article!
5. Over Fertilization
Pothos leaves turn brown when overfed with fertilizer. This is due to fertilizers’ strong tendency to react with salts and accumulate in the soil. The fertilizer buildup prevents the proper distribution of water and nutrient resources in the plant.
Browning Location: Leaf margins and tips of pothos leaves.
There are two ways you can keep your pothos from turning brown due to fertilizer salt accumulation, all while ensuring and promoting good plant growth and development.
1. Fertilizer Should Be Diluted
Begin applying fertilizer with a diluted solution. Try to observe the first few fertilizer feedings while doing this.
If the pothos plant responds well (it does not dry out or wilt), keep diluting to that ratio.
2. Select Organic Fertilizers
Because organic fertilizers are not as strong as inorganic fertilizers, salt and mineral buildup is not a problem. These options can also decompose into the soil.
Even better? Organic fertilizers, such as worm castings, fermented plant juice, and fermented fruit juice, are a much cheaper option.
Know more about the differences between fertilizers in our article on organic and inorganic fertilizers.
6. Sunlight Exposure is Too Low
If placed in an area with limited lighting, the pigment responsible for the green color in pothos leaves and eventually turns brown. This happens as pothos leaves can no longer synthesize food resources for the plants, fade in color, and start to dry.
Browning Location: Leaf surface starts from the center of pothos leaves.
Putting plants in dark spaces triggers yellowing. Why? Let me first re-introduce you to a familiar friend, chlorophyll.
Chlorophyll is the pigment in our leaves responsible for their green color. Chlorophyll is only activated when sunlight hits them. Thus, if there is not enough sunlight, yellowing occurs. Browning happens as a result of a combination of lighting and soil factors.
Pro Tip: When you notice your pothos plants going towards the light, that is a sign that they are longing for more light. Thus, it is an indicator of the location you need to move them to. You can also use LED grow lights to supply supplemental lighting to your pothos.
But what is the best location for your pothos plant? More details will be discussed in the next section.
7. Sunlight Exposure is Too High
Too much direct sunlight will lead to drying of pothos leaves and make them turn crispy and brown. This is also known as leaf burning.
Browning Location: Leaf margins and tips of pothos leaves.
Very high temperatures could cause leaf burning in pothos that commonly starts at the leaf margins. To prevent this, the temperature must be maintained from 70 to 90°F for optimum growth.
Pro Tip: Locate your pothos plants in east-facing windows or near a west-facing window to avoid direct sunlight.
Take note that pothos plants should not be placed near a south-facing window (excessive direct sun exposure) or a north-facing window (insufficient sun exposure).
8. Low Relative Humidity
When the humidity is low, pothos leaves do not have an adequate source of water and turn brown. More specifically, without an abundant supply of water, the leaves will become dehydrated.
Browning Location: Leaf margins of pothos leaves.
A relative humidity of 50-70% must be maintained for an optimum growth of pothos. You can monitor this by installing a humidity meter like this one from Amazon in your room.
Pro Tip: Use a diffuser or humidifier to make your indoor garden more humid. Rather than essential oils, fill it with distilled water.
If you are growing pothos indoors, you can consider getting the humidifier below on Amazon.
9. Root Rot
Browning in pothos plants can be attributed to root rot. When root rot develops, the root system has a slimy texture. This slime prevents water from flowing upward through the plant system, causing the plant to become dehydrated, dry out, and the leaves to turn brown.
Browning Location: Leaf surface, starts from the center of pothos leaves.
Infection typically begins in the roots and spreads to the leaves and all through the plant. Pothos leaves turn dark brown to black due to Phytophthora, the fungi responsible for root rot.
Pro Tip: Pothos plants showing signs of root rot must always be discarded. Because Phytophthora is easily carried through water, watering it less often will aid in disease prevention.
10. Bacterial Wilt Disease
Bacterial wilt disease commonly results in browning for pothos that are grown from cuttings. Besides turning brown, the plant also stops producing roots. Ralstonia solanacearum is the causative agent of bacterial wilt, and it excretes an ooze from wound areas of the stem.
Browning Location: Leaf surface, starts from the center of pothos leaves.
The challenging thing about this disease is that bacteria can enter the plant through leaf damages such as insect bites and wounds. Thus, the tools you use in your garden should regularly be disinfected with ethyl alcohol to prevent bacterial transfer.
Bacterial blight begins with yellowing and progresses to dominate the leaf until it turns brown.
Pro Tip: Keep the following in mind to avoid the development of bacterial blight in pothos:
- Avoid overwatering.
- Maintain a relative humidity of 50-70%.
- Ensure adequate air circulation.
- Try not to get the leaves wet.
- In the event of an outbreak, infected plants, soil, and pots should be discarded.
11. Scale Bug Infestation
Leaf browning could be a sign of scale bugs infesting the undersides of pothos plants. They suck out nutrients from the leaves that lead to yellowing and browning in different spots on the leaf surface.
Browning Location: Leaf centers as spots on pothos leaves.
Scale bugs are tiny, oblong, and flat with a brownish shell-like protective cover. They thrive in hot, dry conditions and typically attack the bottom part of leaves and the areas around leaf nodes.
They suck out portions of the leaves until they run out of moisture and nutrients which caused them to turn dry and brown. This is the reason why scale-bug-caused browning appears as spots.
Pro Tip: Once scale bugs are observed in your pothos plant, spraying it with neem oil can control their population. You can try the one below available on Amazon.
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Pothos Browning: What Does It Look Like?
Browning of pothos can appear as spots or blotches on the leaf surface, tips, or at the margins.
As I have discussed in the previous sections, different causes may result in varying patterns of browning on pothos leaves. So to find out what may be the problems behind dull and brown pothos, closely inspect those leaves!
FAQs
Should you cut brown leaves off the plant?
Yes, cutting the brown leaves of pothos plants is a practical way to improve their growth process. Whenever these leaves are slashed, the plant redirects its reserves, such as water and sugars, to the development of new foliage. Keep in mind to cut down the damaged leaves up until above the node to allow room for new leaves to grow.
What to do with cut brown pothos leaves?
Discard all cut brown pothos leaves. Never mix them into the compost because they might be carrying bacteria or fungi. These microorganisms can infect the compost and spread in the plants.
Can pothos recover from overwatering?
Pothos, once overwatered, can still recover. This can be done by taking the plant out of the pot, drying the soil, and repotting. However, you also need to examine the roots for root rot. If they are infected, remove those roots, then soak the remaining healthy plant in diluted hydrogen peroxide overnight, and repot.
Should you mist water directly on the leaves of pothos plants?
Pothos do not need high moisture, thus, misting the leaf surface of pothos will not help. In fact, too much moisture accumulating on the leaves could heighten the risk of culturing harmful microorganisms.
Summary of 11 Causes of Brown Pothos Leaves
Browning in pothos leaves is caused by over or underwatering, using tap and hard water, overfertilization, too low and high sunlight exposure, low relative humidity, root rot, bacterial wilt disease, or scale bug infestation.
Pothos leaf browning could be in the form of blotches emerging from the center, burning leaf margins, or small spots all over the leaf surface. All these can be prevented by proper management of environmental conditions such as water quantity and quality, nutrients, lighting, relative humidity, and pests.
Sources
- “Overwatering” by N/A in Missouri Botanical Garden
- “The Effects of Calcium and Magnesium on the Uptake of Potassium by Red Clover (Trifolium Pratense L.) and Hybrid Sorghum Grown on Selected Soils of the Red River Flood Plain in Louisiana” by Stevens, M.H. in Louisiana State University
- “Foliage Houseplants, Fertilizing, Cleaning Leaves, Aphids & ZZ Plant” by Bernitz, N. in University of New Hampshire
- “Houseplants Diseases and Disorders” by Kluepfel, M. in Clemson University Cooperative Extension Service
- “Pothos (Epipremnum aureum) Diseases: Identification and Control in Commercial Greenhouse Production” by Norman, D.J. and Ali, G.S. in University of Florida
- “Pothos, Epipremmum aureum” by Mahr, S. in University of Wisconsin-Madison