find a humidifier with a digital humidistat ( like a thermostat but for humidity ) and you should be good . using a timer can be a pain because as your plants grow the humidity is going to change and you will have to constantly adjust the timer .Hello I'm in the process of bettering my grow room.Humidity is low were I live.Don't have a thermostat.Getting my air from inside.Is the trick I need adding a humidifier and set it up on a timer to try and keep it 50 to 65%?