Lighting setting

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I have a 430 watt HPS light and have a couple of plants on 24 hour light and was woundering how long to keep them on 24 hours, then what. I was told to do 24, then 18 - 6 then 12- 12 and also 24, then 12 - 12 what is True?? please help

i was thinking of this 24 hour light for a month then trying 12 - 12 for another month would that work?
i would cut them back to 18-6 now and let veg to 1/3 their desired ht. then go to 12-12.
I go from 24 on to 12/12 once ther 1 and a half feet tall
Adam. I think the reason why you have been told buy diffrent people to do diffrent things, and here in the case of WeedDog and Cincy boy, is the fact that every plant is diffrent. Some react to diffrent things. Some will respond to 36 hours of darkness before switching to 12/12 and some wont. Some will grow faster under 24 hour lighting, some will grow faster under if they are given a rest for a little bit 18/6. And most of it varrys alot between human error, plant strains, type of growing, type of lighting, light spacing, growing method as in scrog , SOG etc.

So I would have to say to just experiment, and see what works best for you. By the second or third time you'll know what your plants respond to best.

Good luck.

Oh and for my opinion. I use 20 hours on and 4 off. Then 36 hours of darkness (so the plant has a good stock pile of the enzyme that triggers flowering before the light is given back to it), then 12/12. I do this because in high school one of my botany teachers said once that no plant can use more then 20 hours of light a day. He said a plant must use the sugars and light energy it builds up and stops photosynthisis <sorry I cant spell> to do this. Or something close to that. It was 15 years ago. But I do remember the 20/4 thing correctly. Is he right ? I dont know. But it seems to work for me.
cincy boy said:
I go from 24 on to 12/12 once ther 1 and a half feet tall

Just wondering what the final height would be when you harvest?
with the bagseed im growing now they get to be like 3---3 1/2 one time one got a few inches away from 5 feet that had the most buds

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