18/6 to avoid outdoor starts flowering?

Was wondering for those starting early for the great outdoors , do you run 18/6 before going outside? I’ve had mixed success with 24 hours of light , some have gone into flowering and yields have been affected …Wondering your thoughts …


If your plants get less light outdoors than indoors there’s a good chance it will trigger flowering. You’ll want the indoor time to match your outdoors. Or you could get a cheap light to provide supplement lighting outside to prevent early flowering.


:point_up_2: What he said. We get those rope lights and hang them above the plants.


Is there a better schedule than 18/6 ? Thinking June 1 will be safe regarding not triggering budding under 18/6 …

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I 24 hour 1 week , 18/6 a couple than sit them outside in there pots for a week then plant in the ground

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I’m not sure what you mean by a better schedule? We put them out a few weeks before solstice, hang rope rope lights to keep them from flowering, and then start pulling tarp after solstice (if that answers your question?) You might check this site for available light per day:



I have them under 24 . Bout to go to 18/6 . I’m only concerned about the older plants , they’ve already shown sex under 24 hours …

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If there already showing sex there big enough to start hardening off outside I would still leave them in there pots for a week to let them completely acclimate before planting…if you guys are talking about light dep I don’t know anything about that

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The rope lights are a good idea , I’m not in a legal state to do that outside though …

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I’m not doing light dep :blush:


Oh gotcha. My only outdoor experience is in greenhouses. I’ll have to defer to others. :v:

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Than yeah the week they spend in the pot will help them adjust to the light and temp difference and allow the plant to spread those roots instead of being shocked fluff the root ball up a little with your fingers like running them through hair I do this with all plants it helps them establish roots quicker an old trick from when I planted hundreds of trees a day


I researched and it seems 16/8 works . Anyone done this ?

I don’t know if this helps you but I veg under 16-8 and it works fine for my indoor.

I’m curious when I can mine outside also. Is it too early in the season? Its currently 13-11 where I am.


I don’t put anything outside before Mother’s Day where I’m at …


I run 17/7 and when I take plants outside they flower unless they get the same 17 hours of sun. For early starts to the season, I’ve only seen people who do the supplemental lighting not have early flower issues. If your outside light is 18 hours then it should be fine.


I do 16-8 for anything I’m starting for outdoor. It is just over what will be right at 14 hours sunlight when I put out. That should allow you to set out without shocking them much. I always try to harden off a few days before transplanting but it’s not necessary. I may see a little shock but they recover quick. You may encounter some issues if you are running real early flowering strains. Some of them will want to flower if put out to early. I try and hold them until between mid May and June 1st


I’ve always thought you were safe at around 14 hours light. That is when I put mine out. I set my timer to around the same time as when I want to put the plants outside. Google “sunrise sunset calendar” and find the sunrise and sunset of the day you put them out.


I would put them out right after your frost free date. My experience is the bigger you grow them and the earlier u put them out the better in the long run, and u will be able to harvest 2 to 4 weeks earlier as well. I start mine the beginning of March and put out 3rd week of April and I’m in zone 6. Hope this helps


I keep them under 17 indoors and cut to 16 a weak before they go out. I wait untill I have at least 15 hours of light outside which is around June 1st where I am. I also keep the babies intended for outside further from my t5 so they are getting weaker light.They lose a few hours when going out but gain intensity so it norm works out. I’ve seen alot of babies esp clones that were grown under intense lights flower when put outside esp if root bound, a good strong doss of veg food also seems to keep them headed in the right direction.