Yellowing and sunburned Pothos leaves

(Question)

I have had this pothos in this same pot for 6 years. I noticed this winter that many yellow leafs were appearing on a daily basis. It was possibly due to my over watering and it basically sitting in water. So I pruned it, removed the leafs, cleaned the stems which were covered in over fertilizing residue and white crusty bits. Then put it in bright sunlight for a few days and this has now appeared. Is this a disease, pest or sunburn? Please help!

(Answer)

Hi there1

Thank you for your question to Toronto Master Gardeners.

Your Pothos has lived in the same pot for the past 6 years, so there has been significant root crowding. Growing houseplants require larger containers and fresh soil every once in a while. Otherwise, the roots have nowhere to go.  Combine that squished feeling with overwatering, and you have a recipe for root rot. The yellowing leaves are a result of this condition and possibly too much fertilizer. You mentioned that you moved it into bright sunlight a few days ago. From what I can see, you’re right about plant sunburn.

You may be able to save your plant with a few simple steps.

  • Remove it from the sunny window.
  • Clip off a few (not all) of the yellow leaves, dipping your scissors’ blades into rubbing alcohol or a mix of 1 part bleach to 9 parts water after each cut.
  • Find a clean container one size larger, with good drainage. Add fresh indoor soil mix.
  • Prepare a space for the Pothos in the centre of the new container.
  • Remove the Pothos from the old container and clear soil away from the roots.
  • Inspect the roots to see if they are still alive. If they are rotted out, you may need to compost most of the plant.
  • Try taking a few healthy cuttings and rooting them in water to make more plants.
  • If the roots look sturdy, place the plant in the hole you created and gently add more soil to cover them.
  • Place it in a location where it receives moderate light, not direct sunlight.
  • Clip off the remaining yellow leaves slowly over the next weeks and months. Your plant needs foliage to survive.

Give it the best possible care and see what happens. Two excellent resources for houseplant care are The New Plant Parent, Darryl Cheng. Abrams, The Art of Books, New York, 2019, and Complete Guide to Houseplants, Ortho Books.

5 April 2021