Soft Pothos Leaves. So, what are the reasons behind pothos leaves turning black? When a plant is rootbound, it causes the plant to start turning yellow and have curling leaves.

Pothos plants perform best when they are watered regularly and when you allow the soil to dry somewhat between waterings. Potassium is lacking when the leaf has yellow edges, so you need to assess the soil carefully. Move the pothos to a position that gets bright, indirect sunlight for at least 6 hours per day.

Fertilizer Is Not Something That Most Pothos Require Very Often If At All.
One factor you should always check is drainage efficiency. I highly recommend placing it out of the reach of children and pets. To save yours, follow these steps:
Remove The Infected Leaves And Petioles, The Parts That Connect Leaves.
While curling leaves due to underwatering are the most common cause for pothos leaves curling, it’s the overwatering that can lead to your plant dying a whole lot faster. Pothos leaves can turn brown due to a variety of factors including pest infestation, fungal diseases, improper fertilizer application, too much or too little light, and other environmental factors. The best trick is to let the topsoil dry between watering, and you can check it by feeling the topsoil.
The Usual Rule Is To Water Your Plant Only Once A Week.
Your pothos prefers soil that is consistently moist. If the roots are mushy, soft, and black, root rot has taken hold. Overfeeding the pothos with fertilizer.