Is a shaft of light in marijuana grow room bad?

I’m using my closet as a marijuana grow room. Between the door and the wall, there is about a 1/4-inch slot that light can pass through. Will this affect anything during the flowering period?

It’s possible. It really depends on the amount of light that gets into the marijuana grow room. Even a tiny sliver of light can interfere with the flowering period. To prevent problems, it’s in your best interest to close the crack. Using duct tape and/or a black polyethylene curtain to cover the opening are two easy options. You should keep this material over the crack’s full area to avoid any accidents.

Light pollution is one of the worst things during the flowering period. Sometimes, it can merely stultify the actual growth of the plants (instead of keeping it in vegetative state). In some ways, this is worse because the buds never become dense.