Help with Philodendron watery and browning leaves

[AnnaWuki]

Hello everyone, I really hope my plant is not dying. I'm really scared, it's my first houseplant and I love it so much. I have a Philodendron Red Emerald, I got it exactly a year ago as a birthday present and it grew beautifully from about 1m to nearly under the ceiling. It was getting too long, so I took some cuttings about a week ago. It has had issues with yellowing (more like orangebrown in this case), but only the old and big leaves near the stem, so I wasn't worried.
Then three days ago I fertilized it for the first time, because the leaves looked dull and not that shiny and deep green as they did in the beginning and I never repotted it, so the soil might be missing some minerals. I used liquid fertilizer mixed in water as instructed. Yesterday I started noticing streaky wet blotches against the light, water was dripping down the leaves and this morning the streaks are even bigger. Maybe it's my imagination but the leaves look like they're even less green and slowly turning orange.

What could the problem be? Bacteria? Root rot? Too much fertilizer? Did I do something wrong taking the clippings? (I cut off a large section instead of just two or three small nodes.Actually, the clippings that I took do not have the watery streaking). I am desperate, I really want to save this plant! thank you!

 

[Jewell]

Taking cuttings will not harm the plant and is a great way to get more free plants. If you are worried about loosing your plant I’d take more cuttings to root.

Look up fertilizer burn to see if this is your problem. Finding professional solutions or from someone here who has solved this problem may come to your rescue. Most house plants don’t require much from my experiences. I have well over a hundred houseplants and seldom fertilize and then only with a very weak watered-down solution. Good luck.

 

[AnnaWuki]

Thank you for the reply. Yes, I think it might have something to do with fertilizer burn. I read up on it and it says it basically dehydrates the plant because it cannot take up any more water from the roots, as the soil is too saturized with fertilizer. The plant is very big so it is difficult for me to rinse the soil thoroughly without damaging it. And I am worried about root rot, as the philodendron are so sensitive to overwatering. I don't know if there is anything else I can do? It has a lot of aerial roots on the higher wines, would it help to spray water to keep the air moist or will it make it worse or even prone to fungus infections?

And you're right, I never thought about fertilizing it because it was growing so well, but the leaves looked dull and not as vibrant. Maybe it had to do with low light in winter, though. Now I wished I hadn't used the fertilizer.

 

[Jewell]

Take cuttings for new plants. That is my goto solution for many plant problems

Although I’ve never done this my daughter often rinses all the soil off the plant roots and repots with new soil. This is how she deals with fungus gnats. It might work for your problem.