I use a closet for my marijuana grow room. Will the flowering period be affected if I turn the light on in the middle of the dark period with the closet door open? Won’t the plants produce too much oxygen if I keep the door open?
Even an almost negligible amount of light can do damage during the flowering period. It can affect bud growth and send the plant mixed signals. Marijuana plants are most sensitive right in the middle of the dark period. If you regularly expose the plants to light pollution, you will end up with immature, loose, and runny buds.
Oxygen is produced by the marijuauna plant only when the lights are on. Light is the fuel for photosynthesis—the process that takes water and CO2 to produce sugars and release oxygen. You can keep the closet door open during the light period every day.
Photosynthesis stops in the dark, but the plants still uses sugars to fuel metabolic processes. Sugars work as an actual fuel for the plant and as building blocks for plant tissue. The plant releases CO2 during this period which is vital for later photosynthesizing. With a closed door, you can trap all that CO2 for the plant to use later.
If you absolutely need to look at the marijuana grow room when the lights are off, you can use a green light. Plants simply reflect any light that is green and they won’t use it to fuel photosynthesis. You can find incandescent and fluorescent tubes with green coloring.