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Question about outdoor daylight effects

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Hi all,


Planning on moving outdoors for the first time. Figure in the next few wks some indoor veggers on 18/6 would be good to move outdoors to let them flower, with about 11hrs of daylight currently.


I was a bit worried the lengthening days might affect flowering but it seems the max daylight hours locally, even at the dec equinox are maybe 13.5hrs max. So I can't imagine the amount of increasing light over the next couple of months will make them revert to veg.


My question is about plans to do some outdoor growing in the summer. With only maybe 13.5 hrs of daylight (in this region) max in summer, how do plants get to any decent size vegging before they start flowering? Wouldn't they all just go to flower from seed? I could try some autos, but would like to have some outdoor photoperiod plants too.

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welcome here Kbomb :peace:



So I can't imagine the amount of increasing light over the next couple of months will make them revert to veg.

dont bet on this , depending upon strain, small incremental increasing daylight hours will really fuck the plant over


imo  the plant uses its first-day-lenght to equate all following life events

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Thanks Frazz,


You have me a little worried now! That, and the fact that after posting, I went back to review the daylight chart and realised that they divide 'non-dark' periods into daylight, and about 3 different types of twilight! So in fact at Dec 21 there is only 7hrs of 'night'. And I assume it's total or at least night dark that is required for flowering, not including any type of twilight (hence total blackout for indoor flowering).


So yeah, now i'm not so sure that's a good idea going out just now. Figured I could free up some space inside getting some newbies ready for outdoor. Oh well, i'll finish them off inside.


My reading finds lots of people who recommend starting plants off indoors til they're a bit bigger and stronger and able to cope with the sun outside. I always start 18/6 from germination so this still leaves me puzzled about how to do that transition. If I go from 18hrs of light to say 14hrs bringing them outside, they have a sudden reduction in light hrs, only to then have a slowly increasing amount of light (assuming I do this in Spring and the days get slowly longer til Dec 21). So won't this mess them up too? Sounds like I ought to start them off indoor, put them out on Dec 21, and then let the slowly dwindling day length lead them to flower. Won't growth be an issue that way though? I want monster big plants with heaps of veg time outdoors to let them get massive!

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So here i am flip-flopping and looking like an arse, not having read enough before posting my Q! Apologies all. I do generally try to find my answers by reading, but am reasonably new to this site - more of a 420 magazine reader but I like this site for 'local' experience and thought this was the place to find more relevant outdoor grow info.


The thread here called "Growing outdoors and understanding light hours" is awesome but has now confused me more! There are a few there who seem experienced and successful at putting plants out around this time of yr after 18/6 inside. So now i'm back to thinking maybe I ought to try it. Mine are indica dominant (dinafem OG kush and medicann blue blood) so that will help. Topped once, some LST bending in action. I could def use the indoor space/lights to get some other plants started and also going away for a week in the not too distant future and always feel a little unsettled leaving indoor stuff running (always worry i'll get a call saying there was a big fire!) so having everything off and outside would be good. I also have a smaller TGA spacebomb a few weeks behind these two, which could use the lights that these two are using, to develop a bit more quickly.


Who reckons i'll be safe and they'll just flower and continue to flower; and who thinks they'll start re-vegging?

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hey Kbomb , i can only tell you what outcomes i have had.

Ive done what you are wanting to do for several years running

i have found Indica strains are more inclinded when it comes to re-verting to veg

sativas were not so likely to re-vert. it seems somewhat strain related imo

some plants started inside on 14hrs then put outside late Sept- early Oct (latitude 30 S)

manage to stay in veg, whilst i had others under same light start to re-veg


another factor i believe is very relevant is Intensity of light indoors ..

meaning , the seedlings i had indoors were on the very edge of a big light,

so they didnt recieve intense , strong light, moreover just enuf light to stop stretching

but not enuf to make them really take off with fast growth, it was the majority of these seedlings

which did not revert to veg.


your other worry about plants not getting big enuf by just begining them outside

when i take plants out to the garden in October they have Nov, Dec, Jan and 2 weeks of Feb before flowers appear

this is enuf time for plants to grow up to 2+mt /4 pounders dependent on strain, sativas tend to get the biggest


so thats my exp. for you to take on board , just get more opinions and more reading

and im sure you will make a good run of it


no doubt there will be some here who just poo-hoo my comments

but there are always ' smarter than thou ' kunts around arent there

guess we cant all be so clever


good luck with 'em :peace:

Edited by Frazz
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Depending on your latitude, putting indi doms out now will flip them into flower and they should (not guaranteed) finish up without any problems.  I put a couple out in August a few years back and they finished up fine, but I had started them into flower before putting out.


If you're looking to start outdoor plants off under lights before putting them out for a full season grow though, my advice is to veg them indoors on a 15/9 light cycle and not put them out until mid to late October, otherwise the sudden increase in dark hrs can trigger some strains into flower.


You really don't need to be in a huge rush to get outdoor plants started as they get plenty of time to veg even if you don't put them out until November, we've had some growers here have good sized plants outdoors that weren't started until December.



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i have found Indica strains are more inclinded when it comes to re-verting to veg

 thanks again for your thoughts Frazz - funny I found from reading that most seem to say sativas are the more likely to reveg in this situation because of the longer flowering time. As you say, one can but read and read, then ultimately go for it and learn from experience. I think overall i'm going to go for it and see what happens. I'll be sure to update here what transpired, for those curious, and for those seeking similar advice in future.


Also thanks SirPsycho for your thoughts. Interesting ideas and sound advice.


FWIW, i'm lat 25 and using smallish LEDs inside. My best lights are 2 x G.O.D-1 lights from Budmaster (UK). But they do the trick and I have managed about 1.5oz of decent med from one plant in a small box (less with more than one plant obviously due to size and light constraints). Also have a bunch of 2" T5 but I find these make my little boxes pretty hot and are pointless any other time other than winter.

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Hey there, update time.


So I switched all 3 from 18/6 to match the current outdoor light (daylight + 'civil' twilight). Had been running lights overnight to minimise temps so the 'switch' involved letting the girls go 24hrs dark and flipping day/night for them.


just cut down the last of them. They all flowered beautifully.


My lesson: Success at germinating and vegging indoors under lights 18/6 then bringing outdoors to flip into flower mid-Aug with harvest early-mid Oct.

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