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photoperiod and flowering

Have a quick question concerning photoperiod for some of the experienced folks here on icmag. bare with me, as im not sure exactly how to express my question.

indoor gardens operate with a veg area with short nights, and a flower area with long nights. And it is the long nights that trigger for a plant to flower.

typically, in an indoor garden, people use 12/12 to put the plant into flowering. Outdoors is another story. As the nights get longer, eventually they become long enough that the plant begins to flower. The amount of night it takes to begin flowering varies from plant to plant.

This leads me to my question/questions...

last year i helped a friend who grows outdoors. he had lost some plants early in the season due to weather. i gave him a few clones to take out just as his original plants began to show sex. this of course made the clones flower immediately because the nighttime hours were long enough. which gave him some nice small plants right on schedule. no problems. exactly what we were expecting.

in this example the nights are getting shorter each evening by a minute or so.

my question is, could this technique be used BEFORE the beginning of a season? i would assume that as long as the hours of night stays higher than the "critical flowering point" everything would be fine. but im not sure if the increasing day time, rather than losing a minute in the fall, would make it not work.

i figure if i found a very cold hardy strain and put out mature clones early enough that i could give it 8 weeks to flower before the day length made it begin to re-veg.

would this work, or would the day to day increasing of day length cause reveging despite the number of night time hours??

sure hope that makes sense.....
 
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i had never given light spectrum any thought. Thanks for bringing that to the table.

what sorts of negative effects do you think the different light spectrum would bring about? just less mass? or a drop in quality?
 
i will also add that i know the easier option would be starting a fast, cold-hardy autoflower indoors from seed and transplanting outdoors early in the season...

...then again, i have no experience with auto's so maybe that wouldn't work either for some reason!
 

aridbud

automeister
ICMag Donor
Veteran
It appears to me to be quite laborious, changing a minute per day (if I'm reading this correctly). Indoors a good 18/6, then 12/12 or 13/11 for flower cycle.....rarely fails.
 

Donald Mallard

el duck
Moderator
Veteran
I think the problem will be the amount of daylight hours you have ,
when its cold and days are short , they wont flower very well at all comparative to what one would be used to in a particular variety in ideal conditions .. ..
the slight increase in hours during the day wont matter as much ,
unless your growing tropical sativas , which sounds like your not ....
 

waveguide

Active member
Veteran
arizona.. haven't myself but it is attested that a short flowering harvest can be run in spring since/when it's warm enough. iirc threads mention getting them in the ground by march. think i've seen spring blooms further north in greenhouses?
 
Donald. I assumed there would be a loss in yield due to the colder, less than ideal conditions. However, there are also some positives such as no bugs in the cooler spring weather. Also, I would assume that Leo isn't flying around looking in the non-peak season due to funding issues.

Do you think the stress caused by the colder conditions could lead to hermis?
 
Thanks for the input waveguide! That's what I'm talking about. It seems like in my climate (looking at last frost dates and day length) that I should have enough time to get a harvest in before the days become too long. Plus, now that I think of it, once it getsdone flowering I may be able to leave some of the plant behind and let it revert back to veg for a fall harvest? Even if the reveg stays small, that is fine.

Hmmmm.......
 

aridbud

automeister
ICMag Donor
Veteran
I think the problem will be the amount of daylight hours you have ,
when its cold and days are short , they wont flower very well at all comparative to what one would be used to in a particular variety in ideal conditions .. ..
the slight increase in hours during the day wont matter as much ,
unless your growing tropical sativas , which sounds like your not ....

Have had friends start early....when ground was still too cold.....disproportionate amount of males and hermies seemed to be the outcome. That was in temperate climates of CO/NM/TX. Same goes for autoflowers starting early with soil temps under 50F, light under 12 hrs. a day.
 

Crusader Rabbit

Active member
Veteran
People have successfully done what you're describing. I suggest looking through comments in threads discussing light depreciation in the Greenhouses forum. I specifically remember someone talking about doing it outside in southern California.... said it wasn't the greatest, but still worth the effort to grow and harvest a crop before the spring planting.
 

Ph-patrol

Well-known member
Veteran
Have had friends start early....when ground was still too cold.....disproportionate amount of males and hermies seemed to be the outcome. That was in temperate climates of CO/NM/TX. Same goes for autoflowers starting early with soil temps under 50F, light under 12 hrs. a day.

I have personally found that a stressful veg will bring on a much higher male population.
Im glad you posted this,I don't think many growers believe this theory.
In indoor grow I use lower light to reduce heat and keep Fert at a beneficial amount.I Increase light&fert wattage as plants transition in size and when start to flower.

Sorry I'm off subject
 

aridbud

automeister
ICMag Donor
Veteran
People have successfully done what you're describing. I suggest looking through comments in threads discussing light depreciation in the Greenhouses forum. I specifically remember someone talking about doing it outside in southern California.... said it wasn't the greatest, but still worth the effort to grow and harvest a crop before the spring planting.

Let them experience for themselves. Did several runs in greenhouse.....starting in March....more males.

Holding off until early April....much better results. However, talking areas where it's cold, snow, etc. Warmer, drier climates like California probably reap a different experience.

Worked in commercial greenhouses, too....herbs, annuals, perennials....things really didn't start happening until late March.
 

Betterhaff

Well-known member
Veteran
It’s not just the length of darkness, the changing or increase of light hours in the spring will have an effect on the plant hormones. Sure they will go into flower if you put a clone running on veg cycle outdoors in the spring when light cycles are closer to flowering cycles. But as the day length increases it affects how the plants react…they will basically be fighting to reveg.

I’ve grown plants on window sills thru the winter (year round in some cases) due to lack of space and just trying to save the genetics. It’s funny, they will go into flower in the fall and then seem to stall in winter but will then again begin to flower in late winter/early spring but as the day length increases they revert back to veg. Of course there wasn’t anything in regards to yield, the growing conditions were not optimum for that but as I said I was just trying to save the genetics.

I know in the tropics Spring harvests are possible but the light cycle changes are not as dramatic as in temperate climes (along with things like cold and frost).
 
Thanks everyone for your input! I don't have much experience in the great outdoors, thus me trying to learn. Seems like from what people are saying that I'm probably better off just scrapping the early crop idea.
 
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