For plant owners, there's nothing quite as scary as root rot. And because it's a common problem in many houseplants, you're likely to experience it at some point in your life. Root rot happens when your plants have been watered too much or have been sitting in excess water for an extended period of time. If you notice the leaves on your plants turning yellow, this is the likely cause. But a simple solution of hydrogen peroxide and water can bring your plants back from the brink. The hydrogen peroxide will bubble, giving your plant's roots the oxygen they need!