Change light time or stay the course for autos?

I’m growing autos indoor. I’ve read a lot of different opinions so I’d just like yalls. I’m on 18/6 now just starting flowering, should I adjust my light schedule or leave it the same. Probably another dumb question to most this is my first time with autos and I just want to get it right. Thanks in advance…

Welcome to ILGM forum. There are no dumb questions.

No need to change the lights for Auto’s flowering. You can keep it on 18/6 or use 20/4 for the entire grow.

I would highly recommend that you download Robert’s Grow Bible. It is free and you can get it from the website. It helped many of us at the beginning of our growing. It gives a lot of good information.

Thanks @TxGrowman. I had read that when flowering starts to go down to 12/12 but none of them really gave a good reason to do so. Ilgm has helped me every step of the way through my 1st indoor and 1st experience with autos and I couldn’t be happier with my girls so far. Much better than I expected…
I downloaded the grow bible back in February when I was waiting on my “beans” to arrive it has been very helpfulIt. This is my 1st time with Ilgm and I’ll never use another site. From A-Z it’s been a very pleasant experience.


I ushally grow autos however i have recently well infact am close to finishing my first ever reg grow which has been a great learning experience however i think i will stick with the auto’s. Now auto can handle the 18/6 from start to finish it makes no difference i think however thy are still plants so dark time is good for them 18/6 just gives them extra light to grow with. But thts one issue you dont have to worry about with autos. Thy are very difficult if u do it wrong as u cant heal them like u can with Auto’s. Well u can heal them its just alot harder since thy are on a countdown clock u cant slow them down or reveg thm to help thm get better if it goes wrong. And use only 25% nutes to start with and dont go higher than 50% nutes. For examlple reg or Feminized strains get say 4ml grow 4ml bloom and 4ml micro advanced nutrients per 1litre of phd with autos i would give thm 1ml per litre for a couple weeks then slowly increase to no more than 2ml per litre but at the first sign of a issue flush them with phd water and let them dry out then start on 1ml per litre again and stick to 1ml if thy are ok with that and not ok with a higher dose. Autos are no different from fem or reg in the sense tht its trial and error until u find the method that works for you i have 2 autoflower grows on here purple express and smokey bear have a look at them thy might have some good info on it tht may help you. If you ever need some help or advice just tag me and al get back to you as soon as possible my friend. Grow in peace and enjoy the journey youll have with these autos my friend.

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Welcome to ILGM

Personaly I used 12/12 but 18/6 is good really don’t matter with them. That’s why I love growing Fem Plants along side the Auto plants because it doesn’t matter with an Auto


Just to clarify, is that 12/12 from the start or 18/6 then 12/12 alongside a photo from the start?

It’s just because this is another of these never-ending arguments and had me looking at an “experiment” or two before long…

Autos don’t care; they’ll flower with 24 hours of light.

Now, I did have one flowering auto in with four photos. However, I only have one grow space. The auto wasn’t quite ready to harvest when it was time to flip the photos, so it had to share a 12/12 cycle with them for a couple of weeks. I harvested the auto earlier this week and got some incredibly dense buds, so she was none the worse for it. The photos are in week five so they have a ways to go, but I got about 8 oz total from this auto and another that I chopped earlier, so my personal stash is well stocked and it kicks butt.


I flower under 12-12 with autos just like photos
Your a plants will do most of the growing at night @Its420sumwhere

What light schedule do you use during your grow?


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He said it, 12/12 flower like with photos.

I myself have a White Haze Auto going under 12/12 now, was around 2 weeks 18/6 then over to 12/12 because of a photo, she’s now 26 days and this is how she’s responded to 12/12 as seen yesterday.

I count 13 clear bud sites on her, the proof will be in the pudding at around the end of next month.

I will actually start mine off 24 hrs till they break soil and let them get started fir a week then I
Switch to 18-6 just like photos
usually put them under a 12-12 at first sign of flower
But i have separate spaces for veg and flower
If your only working with one space you can use either veg of flower schedule
I have found and @Hogmaster has also noticed they do like to grow under 12-12

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White widdow auto on day 47 and no sign of flowering yet, how long till I should see flowers starting?

How long is a piece of string because every plant is different and will do it’s own thing, and that’s before we think of things like the environment it’s in.

Might be worth thinking about putting her onto 12/12 to stimulate flowering, some say that can sometimes be necessary with some autos because of the genetics involved.