Getting an odor?

Soon after lights out I get a “lawn clipping” smell coming out of my tent… at no other time just after light out. Is this just the plant respiration??? Why just at lights out??

1 Like

My humidity goes up sometimes alot then back down within an hour. I watch them constantly my guess is that’s the plants exhaling. I know I’ve been in my tent head first and all of a sudden get a shot of fragrance. I posted a good thread about science now thinks pla is not only communicate but they might also

I never smell it when lights are on, when lights go out it takes less than 1/2 hour and is it thick. Comes out of the exhust system as the tent is closed. Thought it was respiration but not sure as I have never smelled it before this grow. I’m in 5/6 week of flower. Only lasts about an hour or so than go’s away. Just curious if this is normal of a sign of something good or bad???