Black and Brown Spots on Pothos Leaves – What to Do
Are black and brown spots starting to appear all over the leaves of your pothos plant? In general, pothos are low-maintenance houseplants that can tolerate a number of conditions but there can be cases when a change in condition is too much for the plant to handle.
You Have Been Over-watering the Pothos
Over-watering is one of the most common reasons for the appearance of brown and black spots on pothos leaves. When there’s excess water in the potted soil, the roots of the pothos plant begins to rot and die. This, in turn, can cause the leaves to wilt and develop black and brown spots along the edges. If you identify this at an early-enough stage then you can trim out the dead roots and re-pot the pothos plant in dry soil.
Pothos plants don’t need to be watered all that often. You just need to water them when the top layer of the soil starts to feel dry. If the soil doesn’t drain fast enough then we suggest mixing in materials like perlite to the soil mix.
The Temperature is Too Cold
Black and brown leaf spots are also common when the temperature starts to get cooler. Pothos are tropical plants so they do best in room temperatures between 55 degrees and 80 degrees Fahrenheit. Anything below this temperature range will cause the leaves of the pothos plant to gradually blacken.
To fix this, either find a way to make the room warmer (e.g. fixing drafty windows) or re-position the houseplant so that it is exposed to more indirect sunlight throughout the day. If you plan to turn on the heater at a higher setting then make sure the humidity level of the room doesn’t get too low as that can hurt the plant as well.
Leaf Damage from Pests
Brown and black spots may also develop on the leaves of pothos plants due to the presence of insect pests. The common pests that may appear on these houseplants are mealybugs and spider mites. There are natural remedies that can help eliminate these insects.
For example, you can sprinkle a very fine layer of food-grade diatomaceous earth on the plant foliage to kill the pests without resorting to any chemical pesticide products.