Is there any reason to use 12/12 for an auto during flower?

[neneboob]

Been growing with a buddy, and he's convinced we should run the lights at 12/12 during flowering for autoflowers same as photoperiods. I cannot find any resource that says 12/12 is better than 16/8. Anyone care to throw their 2 cents in? From what I can find it just results in less yield, and taller plants. The only possible benefit I've found is that it helps the room not get too hot, but we haven't had any problems with temps even on 24hr light.

 

[LoveGrowingIt]

Your buddy is mistaken. There's no reason to change the light to 12/12 for autoflowering plants.

 

[LoveGrowingIt]

I once bought seeds that were sold as autoflowers, but they must have been photoperiod because they didn't flower. So, I had to change the light to 12/12. If your 'autoflowers' aren't flowering as they should, they might not be autoflowers. That happens sometimes.

 

[neneboob]

I once bought seeds that were sold as autoflowers, but they must have been photoperiod because they didn't flower. So, I had to change the light to 12/12. If your 'autoflowers' aren't flowering as they should, they might not be autoflowers. That happens sometimes.

nah they are flowering he's just a really big fan of charts, and the one he's going off of is a photoperiod. I'm just hoping to gather enough info off you smarter folks to help convince him. We were doing 24hr light before and it clearly was stressing the plants, so I think he's just got it in his head that 12/12 is a better DLI for any plan that's in flower.

 

[ArtfulCodger]

I'm another vote for there being no benefit from 12/12 for autos. The whole point of autos is that they're bred to ignore day length.

 

[nekvt1]

We were doing 24hr light before and it clearly was stressing the plants,

If 24 he was stressing then you can either turn the lights down and continue with 24 hrs or keep the light the same and try going back to 20/4 or 18/6.

I personally run 24 hours a day most of the year. During the warmest two to Three months during summer I run 18/6 with my lights turned up a bit.

 

[josefrahl]

I usually do 16-18 hours in veg, and go up to 20 hours in flower. Autos need a lot of light.

 

[gemgrows]

I currently am running 2 photoperiods and 2 autoflowers simultaneously under 12/12 , I increase DLI to compensate for the hours of light missing. But as long as the light is strong enough for your girls they'll thrive and still give u 2-3 ounces for a small plant

 

[neneboob]

I currently am running 2 photoperiods and 2 autoflowers simultaneously under 12/12 , I increase DLI to compensate for the hours of light missing. But as long as the light is strong enough for your girls they'll thrive and still give u 2-3 ounces for a small plant

ayeeeeeeee! I knew I'd find someone running autos on 12/12! we are currently running 2 pretty wimpy 100w LED fulspec at the moment. Could you share what your light situation is to produce that much with the 12/12?

 

[Hsilvas81]

I grow autos and light periods together. So when light periods are ready for flower I keep them all at 12/12. Autos are already set genetically from what I've read. I do feel like 12/12 extends the veg period from my experience. I'm thinking the 24 hours I did prior really stressed out my autos and they would preflower right at the 4 week mark. With 12/12, my autos were going to 6 weeks before they showed their pubes on the stem. One little thing I like to do with my autos is the day after I give them super bloom, I keep them in the dark for 24 hours. They seem to really sprout pistils like crazy this way. My mix of Willie Nelson, Super Lemon Haze and White runtz attached.

 

[OldSchoolest]

Been growing with a buddy, and he's convinced we should run the lights at 12/12 during flowering for autoflowers same as photoperiods. I cannot find any resource that says 12/12 is better than 16/8. Anyone care to throw their 2 cents in? From what I can find it just results in less yield, and taller plants. The only possible benefit I've found is that it helps the room not get too hot, but we haven't had any problems with temps even on 24hr light.

No way.

If you’re gonna run autos, ALWAYS give them AS MUCH light as you possibly can!!

You need maximum photosynthesis because you have no say in how that plant grows in a lot of ways ha ha.

It’s gonna do what it wants, and your job is just to make sure it has everything that it needs to do it!

 

[OldSchoolest]

Actually…

Check out @autopotamus on instagram.

It’s either that or autopotomus hahaha

But his autos always pull a pound per plants

 

[gemgrows]

ayeeeeeeee! I knew I'd find someone running autos on 12/12! we are currently running 2 pretty wimpy 100w LED fulspec at the moment. Could you share what your light situation is to produce that much with the 12/12?

So believe it or not, the first 5 weeks I used the vivosun Areolight SE 100w led . But I just switched that one out for the 150w Led. First 4 weeks both photos and autos were under 18/6 . I flipped a week ago . And just upgraded to the 150w 3 days ago. Been running organic using Fox farms as soil and Gaia Green for added amendments. Nothing else .

 

[gemgrows]

No way.

If you’re gonna run autos, ALWAYS give them AS MUCH light as you possibly can!!

You need maximum photosynthesis because you have no say in how that plant grows in a lot of ways ha ha.

It’s gonna do what it wants, and your job is just to make sure it has everything that it needs to do it!

I disagree . Its less to do with hours of light and more to do with your DLI , daily light intake is a measurement of total amount light given in a day. There for, increasing your light intensity 35-40% and flipping to 12/12 will provide the same amount of light to the plant. Growers do it all the time . It's all About compensation and balance.
Photos for reference . Flipped lighting to 12/12 8 days ago. End of week 5 since sprout.

 

[gemgrows]

I grow autos and light periods together. So when light periods are ready for flower I keep them all at 12/12. Autos are already set genetically from what I've read. I do feel like 12/12 extends the veg period from my experience. I'm thinking the 24 hours I did prior really stressed out my autos and they would preflower right at the 4 week mark. With 12/12, my autos were going to 6 weeks before they showed their pubes on the stem. One little thing I like to do with my autos is the day after I give them super bloom, I keep them in the dark for 24 hours. They seem to really sprout pistils like crazy this way. My mix of Willie Nelson, Super Lemon Haze and White runtz attached.

I'm doing the same thing and honestly have no complaints so far .

 

[Magnumsmydog]

I disagree . Its less to do with hours of light and more to do with your DLI , daily light intake is a measurement of total amount light given in a day. There for, increasing your light intensity 35-40% and flipping to 12/12 with provide the same amount of light to the plant. Growers do it all the time . It's all About compensation and balance.
Photos for reference . Flipped lighting to 12/12 8 days ago. End of week 5 since sprout.

I would agree here, only thing that I wouldn't like is that it would cut time I can spend on them when things get busy with life. I'm no expert this is just my 2 Penny's worth.

 

[Hsilvas81]

I disagree . Its less to do with hours of light and more to do with your DLI , daily light intake is a measurement of total amount light given in a day. There for, increasing your light intensity 35-40% and flipping to 12/12 will provide the same amount of light to the plant. Growers do it all the time . It's all About compensation and balance.
Photos for reference . Flipped lighting to 12/12 8 days ago. End of week 5 since sprout.

I agree here. Additionally, I read a plant can only absorb so much light energy in a 24 hour period. Also read once the trichomes are fattening up, having a 24 hour light on them degrades the trichomes faster than full bud maturity. I have over a dozen grows under my belt and have had ones that went way south so it's been a journey.

 

[neneboob]

I disagree . Its less to do with hours of light and more to do with your DLI , daily light intake is a measurement of total amount light given in a day. There for, increasing your light intensity 35-40% and flipping to 12/12 will provide the same amount of light to the plant. Growers do it all the time . It's all About compensation and balance.
Photos for reference . Flipped lighting to 12/12 8 days ago. End of week 5 since sprout.

So then please let me ask you one question from what you've said. If it's all about DLI we can grow 16/8 or 12/12 so long as the PAR is in the right range? We only really have 1 area to grow in, and I expect we will have both veg and flower plants. So would it be fine to run 16/8 and check the PAR to do some DLI calculations so that we don't have to worry about trying to separate the flower and veg plants? then we can just turning the lights up or down, and move the plants closer or farther from the light?

 

[gemgrows]

So then please let me ask you one question from what you've said. If it's all about DLI we can grow 16/8 or 12/12 so long as the PAR is in the right range? We only really have 1 area to grow in, and I expect we will have both veg and flower plants. So would it be fine to run 16/8 and check the PAR to do some DLI calculations so that we don't have to worry about trying to separate the flower and veg plants? then we can just turning the lights up or down, and move the plants closer or farther from the light?

I don't calculate DLI myself. All I've done is increase the intensity setting in on my light 40%. I increase the lighting distance if I notice burning or twisting of leaves . I do see the benifits in measuring those things though. But I depend more on letting the plant show me want it wants. And yes u can have both photos and autos in one space . But keep in mind if your photoperiods are flowering u must keep the 12/12 light cycle on them otherwise they will hermie.if it's auto flowers that are in flower u can be more flexible with your lighting schedule .

 

[neneboob]

I don't calculate DLI myself. All I've done is increase the intensity setting in on my light 40%. I increase the lighting distance if I notice burning or twisting of leaves . I do see the benifits in measuring those things though. But I depend more on letting the plant show me want it wants. And yes u can have both photos and autos in one space . But keep in mind if your photoperiods are flowering u must keep the 12/12 light cycle on them otherwise they will hermie.if it's auto flowers that are in flower u can be more flexible with your lighting schedule .

Well for now we have nothing but autos, and from what most people on this thread have said they typically use 18/6, and 12/12 is more for if there's a photoperiod with them. My whole thought was to make it a bit simple to have plants at different stages, and only having 1 light schedule was so that all we needed to do was bump up the intensity of the light for the older plants.

Thank you for you answer!