Q.My Philodendron Imperial Red Has Brown Spots On The Leaves, And I’m Worried That I Maybe Overwatering It? Or Is It Receiving Too
much light? i water it once weekly when the soil is dry and place it beside a north facing window… it receives bright indirect light from 2/3pm till sunset.
Certified GKH Gardening Expert
Usually, this is from a little too much water. Watering should not be done on schedule, rather, should be done when the soil is completely dry. For this plant, it will be about 3 or 4 inches down the container. Some suggestions will say only an inch, but I find that underwatering is far better than over. A soil probe may be necessary to determine if there is moisture, at all, down to this depth.
Treat with a light fungicide, and carefully measure moisture content to ensure that the plant receives the correct amount of water.
Here is an article that will help you to use fungicides correctly:
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm
This article will help you to care for the plant:
https://www.gardeningknowhow.com/houseplants/philodendron/caring-for-philodendrons.htm