When do i change light cycle?

I’m a new grower and wondering if i change the light cycle on my autoflower plants to 12 hours on 12 hours off. My plants are 6 weeks old now. Thanks!

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autos don’t care what the light do. They will start to flower when the spirit moves them.
But, you can change if u want to save electricity.


Thank you! I turned lights off for 6 hours last night. Lights on 18 hours. Hoping they will grow faster. I got the grow tent set up and better light coming. Plus good fan. They’re happy plants.


They only thing is, most autoflowers start flowering around 5 weeks, but they can take longer. If you’re not seeing any sign of flowers yet, it’s possible you may not have received an autoflower. So if you don’t see flowers pretty soon, you may have to flip to 12/12.

I don’t see auto flowers changing yet. They got a slow start because they were in window for a couple weeks before i bought a grow light. Just got a tent about 5 days ago. They are doing better. I read to change the light cycle to 18 hours on 6 hours off to get them to grow faster. The last 2 nights they liked the light off. I would like more growth before i switch to 12 hours off and 12 hours on. Thanks for your feedback!

I have wedding cake auto flowers. I also have skunk and gold leaf that aren’t auto but 2 weeks old. I have lots to learn but excited about how well my plants are doing. I’m going to continue with 18 on 6 off until they’re bigger than I’ll try 12 on and 12 off. Thanks for your help!


Solid plan. :+1:
As noted above, autos are supposed to flower at around 5 weeks but lately I have seen lots of complaints that they won’t start on their own.
Sometimes I wish mine would stall like that so they get bigger.
Keep them on 18/6 and if they decide on their own to flower, then no change is necessary. I have heard other growers that do 6 on and 2 off with autos. It shouldn’t matter but sometimes it does.