Lighting the dark

My girlfriend and I have our flowering space in our walk-in closet. She needs to go in there to get shirts and shoes, and most of the time, the lights are off. Would it be possible to use a green incandescent bulb to illuminate the closet without affecting the dark cycle?

Plants use infrared, red, and blue light to regulate their growth and flowering as well as to power photosynthesis. Photosynthesis is the process by which plants use light to combine water absorbed by the roots and carbon dioxide from the air to make sugar. Sugar fuels the cell’s life processes and is a building block for tissue.

Green light is not used by plants and is reflected back from the leaves. For this reason green light can be used in a dark room. It will not affect the plants’ flowering cycles. Green incandescent bulbs and green fluorescents are available. The incandescent bulbs filter out most light but green. Green fluorescent lamps produce a bright green light.

Readers with grow questions (or answers) should send them to Ed at: Ask Ed, PMB 147, 530 Divisadero St, San Francisco, CA 94117, USA.
You can also email Ed at [email protected] and send queries via his website at
All featured questions will be rewarded with a copy of Ed’s book, The Big Book of Buds. Sorry, Ed cannot send personal replies to your questions.