Lighting What's the best lighting cycle for autos - 24/0, 20/4 or 18/6

[Chilli]

Apologies, as this must have been asked many times before but a quick search on here resulted in nothing.

As the title says, what is the best lights on/off cycle for autos (24/0, 20/4 or 18/6 etc), or does it change dependent on what stage of growth the plant is on (germinating/veg/flower)? Currently I have some 1 week old seedlings on 20/4 (lights on/off), as I'm guessing the 4 hour dark period will help with the root development and the 20 hours light will help leaf development.

 

[agito]

anything above 18/6 is the norm
some run 20/4 for 2 weeks then switch to 18/6

I voted for 18/6 20/4 and other

 

[Jackal]

I voted for 20/4. I would say a good majority of people here uses, myself included.

 

[The Medicine Man]

I have loads of mine on 12/12 'cause I only have 1 room. Some now are on 20/4 as I recently got a blackstar and have that in my laundry room. Only 4 plants under that, tho.

 

[AndyBotwin]

I ran 18/6 from the start on my last grow & tried 24/0 on this one. Adding the 186 hours of light a month didn't seem to make much of a difference, so I dropped it down to 20/4. I'll probably just stick with 18/6 for future grows.

 

[DocGee]

I've been wondering about this, myself. I'm only on my second grow (week 7) and, while I have played around with them and learned a lot, it's only now that I reconsidered my lighting hours. For my entire first grow I went 24/0, and the same so far on my current grow. I figured that since all the literature says autoflowers can go this high, I wouldn't sweat it, but now I wonder what a period of dark might do for them.

Can anybody point to a good source on this? Am I stressing my plants on 24/0? (They look good, except for some nute burn I'm remedying.) I think I'm on target for the estimated yields. They might be finishing a little early, as I've had a small number of amber trichomes (maybe 5% and not the same from plant to plant) developing for several days now. I'll probably chop down one or two right at the end of week 8, but I'd like to see how the rest develop with more time.

OR ... would there be any point in providing a dark period for the next week(s)?

 

[AutoMan]

I've grown autos for years under 12/12...usually cause I had a photo in with'em....with our recent cool spell, I've been running 18/6..seems to beef the girls a bit more.....

 

[Rose]

So far I have grown all my autos on 18/6 and voted accordingly. To me it makes perfect sense that every living creature needs some time to rest and I'm sure I'm stressing the plants enough at the end when I'm somewhat undecided on whether it is ready for harvesting or not, lol. Also, my theory for autos vs photos is that a light schedule from 18/6 upwards accommodates the shorter grow time overall on the autos... (?)

 

[ripster]

:thread:
I voted on the 20/4 and that's my norm. But on my last/current grow. I to, was growing photo's and put 2 other different strains of auto's in w/um...One was the Purple Jem and the other my cross, the Power Pac. The PJ did fantastic under 12/12 lighting. Better than any of their other grows. Now, on the other hand, my Power Pac didn't do near as well.

Now this is my opinion, but both auto strains had different Rudy origins. One did fantastic and the other didn't. So my conclusion is that it seems to depend on the Rudy strain used in making the auto...

Now don't get me wrong, the Power Pac did ok, but just not her usual beefy self. I think more strain testing needs to be done to get a real clarification, but that's how this grow grew for me...

Hope this helps

 

[Griever]

i do 24/7 but i have to i would rather have 20/4

24/7 probley cuts finishing time about 3 or 4 days