The reason the green light works is because plants dont use the green spectrum of the light. Red light would be a bad idea. considering red is the man color of usable light duing flowering.
light from the green spectrum is ok for the plant as this can not be absorbed by the plant, growers use these bulbs just incase they need to get in the grow room in the dark, not saying it should be left on all the time but if you needed to go in there for any reason during dark period green light is the way to go.
The reason the green light works is because plants dont use the green spectrum of the light. Red light would be a bad idea. considering red is the man color of usable light duing flowering.
Nongreenthumb and seedlessone or both right. Plants reflect green light, hence the color of the plant . Im also a firm believer in just leaving your plants be when the lights are off but if you MUST go in there, use a green light and not a red light.
i have never needed to get in there once hence i dont have a green light. If you need to get in the flower room when its dark your flowering at the wrong time of day.