Whats the best Light Cycle for Autos????

auto budz

Member
hi, im unsure what light cycle to use for my onyx. I started on 20/4 now trying 18/6.

what do you find works best?
 

itofficial

Well-Known Member
Im finishing my first autos right now, and don't have much experience growing. But from what Ive read, it seems many don't see a difference in 20/4 and 18/6. I went 18/6 and I think my autos did great under them. They're in the final stages of flowering right now, so I don't know how much the yield will be, but seems fairly high.
 

welshsmoker

Well-Known Member
18/6 till they start to flower then 12/12 mate or 14/10 max, mine seem to prefer 12/12. dont listen to this 18 hr shit, they will go but they take a lot longer to finish.
 

Scyntra

Well-Known Member
I have used 24/0,20/4,18/6. I use 20/4 now. under 20/4 all things being equal they should grow bigger/more bud with more light then with 18/6..in a perfect world anyway..lol.. as far as yield depends on to many factors but 1 to 1 1/2 oz is around norm for mine...
 

Medical Grade

Well-Known Member
I have used 24/0,20/4,18/6. I use 20/4 now. under 20/4 all things being equal they should grow bigger/more bud with more light then with 18/6..in a perfect world anyway..lol.. as far as yield depends on to many factors but 1 to 1 1/2 oz is around norm for mine...

Spot on mate.
 

Medical Grade

Well-Known Member
18/6 till they start to flower then 12/12 mate or 14/10 max, mine seem to prefer 12/12. dont listen to this 18 hr shit, they will go but they take a lot longer to finish.
If you have true auto flowers that are stable and don't need the dark period, then you cut down your yield when going to 12/12
 

Jogro

Well-Known Member
There is zero point to going 12-12 with autos; if you're going to do that, you might as well just use conventional 12-12 photoperiod strains.

The whole point of autos is that they'll flower under more hours of light.

That way, as one example, with 5 weeks of flowering under 20-4, you could "cram" in the same total hours of flowering light as 8 weeks of conventional 12-12. More light during flowering = bigger plants.

Personally, I'd go 20-4 since I think a little bit of 'dark' time probably helps.

The only reason I'd go less than 20-4 with autos was if overhead space/height were a limiting factor, in which case, less light should mean slightly shorter plants (though with less yield).
 

auto budz

Member
Good advice, thx...

if the more light it gets the bigger it gets, wouldn't it be better to go 22/2 or 23/1. Why the 4 hours rest
 

ohmy

Well-Known Member
I know with the auto's i am growing they slowed down when i went to 12/12 . looked up the breeder and they recomended more hours of light . 18/6
 

sonar

Well-Known Member
Joint Doctor recommends an 18/6 light cycle with is autos. I've seen people run them at 20/4 without any problems also.

If you are going to switch to 12/12, why even bother with autoflower seeds?

Lowryder Grow Guide
 

Jogro

Well-Known Member
Good advice, thx...

if the more light it gets the bigger it gets, wouldn't it be better to go 22/2 or 23/1. Why the 4 hours rest
Why do you feel the need to get 8 hours of sleep per night, when you could make due with just 5?

The answer is that "if" there are processes that need to go on in the dark (and that's debatable), you have to give them the time to happen. If you believe that dark time is beneficial, then you'll want to give an appropriate amount of it, and 1-2 hours probably isn't enough.
 

hoss12781

Well-Known Member
I'm running all led now. When I did HPS/CFL I kept it at 20-4. Now I keep it 23.5-/0.5 this is the quickest way I've found to crank them out
 

pilgrim101

Member
you don`t change the light cycle cos they are auto. my white dwarf were on 24hr and after 9 weeks yielded 1 3/4oz dry weight each!
 

madra

Well-Known Member
you don`t change the light cycle cos they are auto. my white dwarf were on 24hr and after 9 weeks yielded 1 3/4oz dry weight each!
thats really good results, have you seen what other people get from the same strain on 20/4? Just wondering if its a big difference. I've used 20/4 and got about an oz from each plant, grew two Pakistani Ryders under a 250w CFL.
 

Jogro

Well-Known Member
Good advice, thx...

if the more light it gets the bigger it gets, wouldn't it be better to go 22/2 or 23/1. Why the 4 hours rest
Why 4 hours rest as opposed to some other number? Good question. You'd think maximum growth would be seen at 24/0, actually.

I seem to remember seeing some study or data suggesting that autoflowers do better with a little bit of dark time, but I can't remember the details and if it was 18/6 or 20/4.

My guess is that the "answer" is that THC is degraded by light, and the plant builds it up again in the dark. So even if you have more absolute plant growth, if you don't have enough dark time, you may not max out THC concentration.

This also suggests that you might be able to get away with 24-0 right until say, 2 or 3 weeks before harvest when THC production is maximized, and then go to 18/6, but again, I've never tried it, I don't have data to suggest this works, and its just a "guess".
 
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