Light schedule question, 20/4 vs 18/6

Gman94

Member
Hey guys, i have been growing my plants on a 20/4 schedule from the beginning, they are now in early pre flower, and i notice they always hang and look terrible the last hour or so before dark, so im thinking maybe it would be healtier to increase the dark period to 6 hours?

Any opinions on this?
 

Dabber68

Well-Known Member
I also run mine 24/0. On the run I just finished the lights over my biggest plant I did 12/12 for 4 days then 3 days dark b4 chopping
 

McStrats

Well-Known Member
What does that do for an auto?
24/0 gets you the maximum amount of growth. Since the life cycle of an auto is predetermined, there really doesn't seem to be any point in not giving them maximum light while you can. They aren't photos so a dark period isn't necessary to get it to flower as it does it already. 12/12 for an auto just means a smaller yield than 24/0.
 

Dabber68

Well-Known Member
The reason I did the 12/12 experiment was just to see if it had any ill affect. For 4 days she got feed the same way and even made on last big drink b4 uptake slowed thats when I fed her last and turned out lights for 3 days then chop chop. I always do 3 days dark so pots dry.
Fat and Sassy is done shes a BEAST in dark for pot to dry then chop chop
 

Gman94

Member
Hmm damn guys, I didnt check up on this.

Im still on my 20/4 cycle. Im surprised how many are saying they are doing 24/0 with no ill effects. my plants are always drooping before the dark cycle, i always veg mine for 24/0 but only for maybe the first 2-3 weeks after that i have always started 20/4.

Maybe i should try sticking to 24/0 once and see what happends.

Im worried my plants arent actually autoflowers tho, im in week 6 or 7 now, i got 4 plants and 2 of them show some signs of pistils but the two others dont have any sign of going into bloom yet.

i have had one autoflower not bloom under 18/6 lighting before, should im thinking im gonna stick to this 20/4 cycle for another week but if i dont see any sign of flowering i think im gonna switch to 12/12, what do you guys think ? shouldnt they be flowering by now ? They are Green crack from Fast buds.
 

H_Aspect

Active Member
Im worried my plants arent actually autoflowers tho, im in week 6 or 7 now, i got 4 plants and 2 of them show some signs of pistils but the two others dont have any sign of going into bloom yet.
That happens. I have 5 and one still isn't showing. It's the smallest of them all by a mile. Same soil, water, lighting... hell, they all broke ground at the same time.

You do you, but if they are autoflowers and you switch to 12/12, you'll regret it later.
 

Gman94

Member
That happens. I have 5 and one still isn't showing. It's the smallest of them all by a mile. Same soil, water, lighting... hell, they all broke ground at the same time.

You do you, but if they are autoflowers and you switch to 12/12, you'll regret it later.
I knooooow, Im thinking ill wait a week or so more and if i still dont see signs of flowering ill go 12/12..
 

Budzbuddha

Well-Known Member
Autos will transition around week 5/6 typically ( day 35 or so ) ....
To give it the BEST VEG would be at a higher cycle so it can push root mass .
Thus 24/0 or 20/4 .... however 18/6 will be fine .

Autos CAN grow under 12/12 ... however it can sometimes keep things smaller sometimes.
However Sativa Dominate cuts will flower nicely ....

Autos love light .... so prepping the plant for the MOST GROWTH DURING ITS SHORT VEG is a given. The week it transitions ( on its own ) it will start sexing ( pistils ) and preflower ( bud sites ) ...

I grew 24/0 and compared results with 18/6 . To me the difference is negligible.
Plants will show LIGHT SATURATION sometimes ( and look droopy ) as it slows down in photosynthesis.... there is a big bag of debate shit when it comes to whether plants NEED dark time.
I don’t change much from regular ( more natural light cycles as found in nature ) meaning probably the only place on the planet where 24 hours happen is Finland .... So why bother other than supplementing the veg growth.

Autos are fickle little shits too , when it comes to feed.
You can plant an auto in JUST GOOD POTTING SOIL and carry it up to transition time ( week 5 )
with just water. Then after it stops / slows stretch , I begin bloom.

One final ... most important of all .... FORGET BREEDER ESTIMATES ON HARVEST TIME.
Most auto growers will agree the plants perform much better when “ run til its done “ .
Most will deliver under 90 days , with a few running a bit longer ( sativas )
 

Gman94

Member
Autos will transition around week 5/6 typically ( day 35 or so ) ....
To give it the BEST VEG would be at a higher cycle so it can push root mass .
Thus 24/0 or 20/4 .... however 18/6 will be fine .

Autos CAN grow under 12/12 ... however it can sometimes keep things smaller sometimes.
However Sativa Dominate cuts will flower nicely ....

Autos love light .... so prepping the plant for the MOST GROWTH DURING ITS SHORT VEG is a given. The week it transitions ( on its own ) it will start sexing ( pistils ) and preflower ( bud sites ) ...

I grew 24/0 and compared results with 18/6 . To me the difference is negligible.
Plants will show LIGHT SATURATION sometimes ( and look droopy ) as it slows down in photosynthesis.... there is a big bag of debate shit when it comes to whether plants NEED dark time.
I don’t change much from regular ( more natural light cycles as found in nature ) meaning probably the only place on the planet where 24 hours happen is Finland .... So why bother other than supplementing the veg growth.

Autos are fickle little shits too , when it comes to feed.
You can plant an auto in JUST GOOD POTTING SOIL and carry it up to transition time ( week 5 )
with just water. Then after it stops / slows stretch , I begin bloom.

One final ... most important of all .... FORGET BREEDER ESTIMATES ON HARVEST TIME.
Most auto growers will agree the plants perform much better when “ run til its done “ .
Most will deliver under 90 days , with a few running a bit longer ( sativas )
So you’re telling me to stick with the 20/4 and wait it out? I was hoping they would finnish before christmas but im a bit worried now, im seing pistils on one plant but the others show no sign of flowering yet.
 

Joe.Grow

Well-Known Member
Personally I will go into 24/0 after they start to flower and do 18/6 veg. Had great results doing this and controlling RH and temp was much simpler. Plenty of people say doing this promotes 20-25% more yield but I’d say try to do a little research and see what you believe is appropriate.

My opinion with 18/6 in veg creates a much more healthy base for flowering and allows the plant to recover for 6 hours. When they go into bloom I want them to flourish as much as possible.
 
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