If you think your philodendron has spider mites, there are a few things you can do: - Inspect the plant carefully for spider mites and their webs. - Use a magnifying glass to help you identify them. - If possible, take a picture of the plant and send it to an expert for confirmation. - Apply insecticidal soap or horticultural oil to the plant. - Remove any affected leaves and discard them in the trash. - Repeat treatment every 7-10 days until the problem is resolved.