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How many hours of light do I need for veg growth?

exile19

Well-Known Member
sorry haven't sent it yet I got a new phone took a picture but to aerospace for me to send going to sprint in a few hope to have it tomorrow for you

but I put them in just water for a couple of days and hope by then you can help me little scared because its 3 weeks and they are only 2 1/2 to 3 inches tall
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Yea a journal will get more people to respond, so maybe you'll get shit I don't know
 

donpaul.p

Member of the Month: Aug 2013
cannabis is a c3 plant, this means it can grow under 24 hours of light or constant light through the whole of veg, but i find it dont give anymore growth compared with other lighting schedules, ive used 24-0 and i wont be using it in the future as i get just as good results using 18-6 or 17-7, so for me i wont use 24-0 but they will grow under constant light,
 

weed4u69

New Member
cannabis is a c3 plant, this means it can grow under 24 hours of light or constant light through the whole of veg, but i find it dont give anymore growth compared with other lighting schedules, ive used 24-0 and i wont be using it in the future as i get just as good results using 18-6 or 17-7, so for me i wont use 24-0 but they will grow under constant light,
Have a question
My plants are 3 weeks old they rang from 2 to 3 inches tall, thing they should be taller. I'm using Dutch Master for food and a sunburst 28 t5 for lighting I started off by keeping the lights about 12 inches away. what can i do if i'm doing something wrong could you please help
 

Dank one

New Member
REAL BIOLOGY HERE lol there are light independent and light dependent reaction in photosynthesis which is the only benifactor of photons (sunlight) to keep it simple it is perfectly acceptable to run on 24 hr cycles during veg simply because "light independent" does not mean it needs to be dark, it simply means that it does not need light. during flower the 12/12 triggers defence mechanisms in the plant to help it repopulate the earth before its death at winter.

MORE PHOTONS = MORE GlUCOSE = MORE GREEN

if you want more detail let me know but these are facts not specualtion or my failed attempt at creating a controlled experiment.
 
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bothteams

New Member
You see that thread for 13 hours. 12 hours, 5.5 off, 1 hour, 5.5 off

I might try that next time to see if it works
 

Dank one

New Member
Have a question
My plants are 3 weeks old they rang from 2 to 3 inches tall, thing they should be taller. I'm using Dutch Master for food and a sunburst 28 t5 for lighting I started off by keeping the lights about 12 inches away. what can i do if i'm doing something wrong could you please help
That is to far away. Floro's need to be as close as you feel they will grow in a few days. Because you will be moving the lights a lot. I would say at most 4 inches above the new growth.
 

polosurfer27

New Member
Awesome, strait forward and factual scientific docuantation. Perfect! Thank you so much for just getting to the point dude, I really appreciate it.
 

Tezkhat

New Member
Hello fellow growers! I`m new to this site, and only at my 2nd grow, the first one resulted in potato quality, so I went back to school for a bit. I`m using now 250 HPS dual spectrum light in a 2x2x6ft closet, and occupied by two white widows. The girls are now 4 weeks old and measure about 5in in height...Had some problems with high temp this summer, but was able to keep it at about 85F, no signs of burning on the leaves. My question is how much longer should I wait before turning to 12/12 (I am on 18/6 since they germinated)? should they be higher than 5in after 4 weeks?
 

grayalien

New Member
That is the idea isn't it?? Derrr! The dood is wasted and I guess you see yourself as a head!?...So, why the hostility bro? I mean, lay off the guy, surely new to forums or not, free speech and all that. Rules??? They are a tool of "The man" ! have a word with yourself mate and wake up.
 

grayalien

New Member
Do your thing mate. I think your idea is mint!!!! I am also new to the forum thing. BUT....I'm not at all new to what I can and can't say, regardless of the format! Share all on forums I heard that was the primary function. Peace.
 

Cellar

New Member
I've tried 6/18 and 0/24 and didn't find much difference so I've settled for 4/20 just to use those numbers.
It works fine.
 

blazeaglory420

Well-Known Member
Kind of old thread but lets finally put it to bed with some relevent information.

For the last 40 years now, growers have been using 16/8, 18/6, and 24/0 (kind of a waste of electricty IMHO) , with SPECTACULAR results... no need to complicate things. Any light after 16 hours on gets wasted mostly as root growth seems to peak at 50mm with 16/8 and slowly diminishes at anything above.

If you're unsure, use 18/6 and be done with it. 40 years worth of experimenting/experience isn't wrong.
 

DaddyKush

Well-Known Member
Guys what’s the most cheapest cheapest effective light I can use for veg
My power bill went waaaaay down when I switched from HID to LED. LED's are a bit more pricey in terms of the initial expense but will save you $$$ on electricity.
 
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