You do need a humidifier. I use a cool mist humidifier that you set the humidity level you want and it automatically reads the rooms humidity and turns on and off at the level you set, and the cool mist it blows when it is on helps keep temps down in a closet. It was at walmart for like $50-60I'm down to 82 degrees in the closet, i have another problem, however. Low humidity is killng my plants!