Hi Jade,

Sitting in water probably caused the soil to stay wet all of the time and that in turn caused the roots to rot. If it were my plant. I would take it out of its pot, get rid of all of the soggy soil (especially any clinging to the roots), and let it sit out bare root over- night. In the morning, feel the roots and see if they appear wet or dry. Re-pot your plant into a container that is just an inch or two larger than the root ball. There must be drip holes in the bottom of the pot! This will allow the soil to dry out quickly when you do water and prevent further root damage. If the roots were wet when you felt them, do not water for about 2 weeks. If they were dry, you can start watering again. Always allow the top 50% of the soil to dry out before watering. Never allow the plant to sit in water.

These plants are considered poisonous and should be kept away from pets and children. Read more about common houseplants that are poisonous in Don’t Feed Me To Your Cat! A Guide to Poisonous Houseplants

You can read more about philodendrons in the Popular Houseplant section of the website.

https://www.houseplant411.com/houseplant/philodendron-selloum-how-to-grow-plant-care