Some say yes, some say no....confused much ?lol 2nd day of summer I put out about 25 girls on my deck. (did this last year also) Next month they will go into flower on their own due to the days getting shorter. I had about 10 different strains out there last year and about 25% of them ended up having either some seeds or alot (but no seeds were visible).the other 75% had none. Possible causes of the seeds: moonlight, star light (Im not in the city btw), a barn light from 10 acres away, a strain that cant do any light leaks or dumbasses going out for a smoke and turning the porch light on. Or maybe all that shit. So its a gamble if you leave it outside really. If you just have that one, imo I would baby that girl and make sure she has total darkness in that 12. I have 25 just outside, a few plants that seed out wont bother me I'll just wax it