The pothos plant is a terrific addition to any home. They can survive in most environments for 10+ years. If you plan on keeping yours around for that long, you need to know that when you see the leaves on pothos turning yellow or brown, it is a sign of distress.
Pothos are not the fussiest of houseplants and there are a limited number of stressors that contribute to leaf discoloration. That’s good news, because it means you can identify what the plant needs, fix the problem, and without needing to do complex soil testing.
The leaf colors and the shade of green is enough to identify what’s making your pothos displeased with its growing conditions, pot, or feeding frequency.
Explore the top reasons for leaf discoloration on pothos plants that are grown indoors:
Start here because almost always, this is the culprit for pothos turning yellow or brown. Over watering will slowly but surely drown the plant, while under watering will dehydrate it.
Straddle between keeping the soil too wet or too dry by watering too often or not enough will stress the plant too.
The key to keeping a pothos properly hydrated is to water it when the top 25% of the soil is dry.
What’s that in Terms of the Pot Size?
How often the soil needs to be watered depends on the volume of soil, and that’s dictated by the size of the pot. Something that’s not as straightforward as we’d love it to be.
The recommended pot size for a pothos plant should have a minimal depth of 4″. However, given every plant is unique, your pothos will have a different size of root ball, so the general guideline is to pot it up in a container that’s big enough to have 2” of soil beneath the root ball and 10” above it.
As the plant grows, the roots expand, so it will eventually outgrow its plant pot. When that happens, it will need to be repotted in a bigger container.
Use the 2” beneath, 10” over rule when your plant becomes root bound. For pothos, repotting tends to be needed every two years requiring a pot in the next size up from its current size.
And Stick with the Same Soil
Pothos do not like change. Repotting can cause transplant shock. When this occurs on houseplants, the acclimation period tends to be under one month.
It won’t matter whether you keep the soil the same or not, transplant shock can be inevitable. It stunts growth, causes yellowing leaves, and sometimes, you’ll see leaf curl and drooping too.
The gentler you manage the repotting process, such as not snipping off too much of the roots, trimming back the leaves by less than a third of the plants overall size, etc. helps minimize the risk of transplant shock occurring.
Not just that, but even if it still happens, the recovery process is faster. Repot with care and plants can recover in just a few days.
How to Tell that a Pothos Needs Repotted?
When a pothos is root bound, the growth rate is stunted. Take a look at the drainage holes and you’ll notice the roots poking through. When you see that, gently tip the plant out of the pot to inspect the root ball.
A pothos is root bound when the roots are densely wrapped around it in the shape of the plant pot. It shows that their growth rate is stunted.
When the root growth is stunted, so will the plant’s growth up top. When roots are constrained, they can’t deliver the same nourishment to the plant as they used to. Yellowing leaves are quick to follow.
The fix is to repot in a suitably sized container.
When Repotting, Inspect for Root Rot
When plants are root bound, the drainage holes can become blocked, which in turn impairs drainage and that leads to overwatering. Left for too long in standing water or soggy soil, root rot can set in.
Plant roots do not rot solely because of water. The saturated soil creates the environment for fungus to thrive.
The two fungal pathogens that infect soil are fusarium and pythium. When either of those fungal pathogens are present in the soil, roots will rot. The more of a fungal infection there is, the more roots will be damaged.
Root rot on pothos will cause yellowing on leaves, and those leaves will curl at night, too. And then, by morning, it’ll miraculously look like it’s fixed itself. Until it happens again daily.
Eventually, the yellow leaves will go brown and it will send the whole plant downhill fast. Root rot kills!
Only if you do not catch it early enough though. The fungus is in the soil so the key to fixing root rot on houseplants is sanitization.
Eliminate the fungal bacteria by replacing the soil, washing the roots, and removing any discolored roots, roots that feel mushy or otherwise aren’t as healthy as they should be. Catch the fungus early enough, and pothos can be revived before all the yellow leaves turn brown from decay and die.
On the Subject of Fungal Infections…
Fungal leaf spot can make it look like leaves are yellow. It’s an illusion.
There are two types of leaf spot that can affect houseplants. Bacterial leaf spot and fungal leaf spot. Bacterial infections are rare on houseplants. For that reason, if you see yellow spots on leaves, treat it as a fungal leaf spot infection.
Leaf spot diseases grow in clusters. The visual appearance makes it look like your plant has yellowing leaves that darken in time. The reality is that you’re seeing a congregation of fungal spores cover the leaf. They prevent photosynthesis so they are going to damage the plant.
Know What Causes Fungal Leaf Spores?
Watering from above, and that’s not to be confused with over watering. Using a watering can to wet the leaves can mean the leaves are wet for longer than they should be.
The leaves on pothos are hydrated from the moisture content in the soil. Correct watering for the majority of houseplants is to water the soil, not the leaves. Leaves may be misted occasionally, but never watered. Especially when temperatures are on the higher end.
Combine excess moisture with high temperatures, and you have a breeding ground for fungal spores.
Fungal spores are on the leaves and not the soil. The fix for this is to prune infected leaves, stop watering from above, and make sure the temperature the plant is in is not excessively hot.
Remember the Obvious Need Plants Have for Sunlight
Pothos, like all green leaved plants require sunlight for photosynthesis. When there’s a lack of light, plants develop chlorosis, a term used for yellow leaves on plants that’s caused by low light levels.
On indoor plants, this is common. More so on one side of the plant, the side that’s more shaded. Keep the entire plant in the shade, and all the leaves can develop chlorosis.
Consider the placement of your plant. If it’s away from sunlight, just moving it closer to a natural light source may be all that’s required. Similarly, too much light can burn the leaves, resulting in a bronzing effect.
The ideal spot for pothos plants indoors is bright but indirect sunlight for most of the day. In the Northern hemisphere, north facing windows provide the coolest temperatures with low light intensity. South-facing windows get more direct sunlight for longer and at a lot hotter temperature.
If you have your pothos near a south-facing window, a UV filter may be required to dilute the light intensity, or just move it back from the window pane.
Pothos thrive best away from window panes. Like on bookshelves, in a corner, mantel, coffee table, bedside table, or even a desk in an office. Make the plant a part of your home, not a window dressing.
Sometimes Though, Leaves on Pothos Turning Yellow or Brown Is Just the Natural Aging Process
All green leaved plants will eventually turn yellow first, then brown. It is the natural aging process. How to tell if the leaf discoloration is natural is when the yellow and brown leaves are limited to the bottom of the plant.
The most mature leaves on potted houseplants are at the bottom. When you see those discolored but all the leaves above it are a healthy shade of green, there’s no need for concern. Prune the yellow leaves and new ones will grow back.
Once you start pruning away mature leaves, essentially stripping away the base layer of leaves, it can leave it looking bare.
One way to make a pothos fuller is by using propagation. Pothos are a simple plant to propagate. Bushy pothos plants are more like a bunch of plants grouped together in one single pot. All you’d be doing is replacing the old mature leaves with new growth.
Brown Leaf Tips Are Caused by Low Humidity
Pothos can throw a curve ball when the yellowing or brown tips are on the leaves only, but the rest of the leaves look fine. That happens when the air is too dry.
You can keep pothos in a low humidity environment, which is why they work great as houseplants. However, if the temperature is too warm for it (resulting in dry air), that is when the leaf tip discoloration happens.
The ideal temperatures for pothos to thrive is between 70 and 90 Fahrenheit.
The above are the growing requirements for pothos.
Nutrient Deficiencies That Cause the Leaves on Pothos to Change Color
New growth will be a paler green shade. Mature leaves will be yellow. The fix is to add a small amount of balanced fertilizer (i.e., 10-10-10).
Causes yellowing around the edges of mature leaves. A potassium-rich food by-product is banana peel. Add some banana peel to the topsoil for the potassium to be absorbed.
With a lack of magnesium, all the leaves remain green but the yellowing is limited to the edges. Not only on mature leaves though. When new leaves too have yellow edges, add Epsom salts to the soil to fix a magnesium deficiency.
A sulfur deficiency is an easy one to notice. The yellowing you’d expect to see on mature leaves at the base of the plant happen up top first.
When you see yellow leaves above green mature leaves, a lack of sulfur is the likely culprit. The fix is the same as magnesium, add Epsom salts. Alternatively, use elemental Sulphur.
Lacking this results in the yellowing being limited to the leaf veins on new leaf growth. The leaves grow in green. The veins that deliver the nutrients from the soil, those yellow. The fix is to add a small amount of zinc sulphate.
If the zinc fix doesn’t restore green to yellow leaf veins, the same issue happens when the soil is iron deficient. Swap out zinc chelates for iron chelates.
The most common reasons for leaves on pothos turning yellow or brown is environmental factors. This includes the room humidity, the temperatures the plant is grown in, and the amount of light it receives.
Pothos need indirect light for most the day. Without sufficient lighting, chlorosis sets in.
Sunlight is essential for photosynthesis to happen. Without it, the plant cannot make its own food so it will not grow, and will eventually starve to death. They only need low light. North-facing windows will work.
Even with good growing conditions, it contributes to how long moisture is held in the soil. The soil for pothos should be fast-draining, in a pot with drainage holes so that the roots of the plant are not in standing water or soggy soil for too long. Temperature and humidity effect the drying time of the soil.
Leave the soil wet or dry for too long, watering problems will stress the plant, and a pothos in distress will show its displeasure with yellowing leaves first.
Leaving the soil wet for too long, and too often, root rot can set in and that is when entire leaves start to turn brown from decay as they die off.
When only parts of the leaves on pothos plants are discoloring, that is an indication of a micro or macro nutrient deficiency. Correct those by adding the appropriate plant food to the soil.
The healthier you keep the soil, the healthier the roots will be. Healthy roots make healthy pothos plants.