How to Grow Herbs Indoors (Without Killing Them) Most indoor herbs don't die from neglect. They die from root hypoxia—a lack of oxygen caused by overwatering and poor soil aeration. To grow herbs successfully, you must solve the balance between hydration and oxygenation. This guide explains how to use sub-irrigation (self-watering) and proper mechanics to maintain that balance automatically. *Parsley in Twisted Square Medium 5" Posie Pot Key Takeaways for Indoor Success Oxyge