Light cycle for fem's and auto indoor

What is the correct light cycle for indoor fem plants? I was told to run 24-7 for the first month then start cycle at 14-8 till flowering and work to 12-12 to finish.

For photos, some start at 24/0 for the first week or two, but then switch to 18/6. Some start at 18/6. But it’s most common to run 18/6 until you are ready to flip to 12/12 for flower. You can shorten the hours daily or weekly, to mimic the sun’s schedule more, but it is really just more work and doesn’t have a real impact on production.

For autos, you can run them 24/0 their whole life. They start flowering when they want, regardless of lighting schedule. You could run an auto next to a photo on an 18/6 cycle, all the way til you flip the photo light schedule to flower and the auto will still do its thing.

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Thanks’ first try on full tent grow. First batch outgrew tent due to improper light cycle and had to go outside, but not doing well. I also just ordered 2 TNB CO2 dispensers to help. I’ve had some mixed results outdoors and want to try and grow in a controlled environment. I’ve used the tent to get them started and after a month take them outdoors. Your advice will also help in getting a good fall batch of outdoor photos. Thanks again. I’ll let you know how the next batch goes. Started 2 Dosido’s 2 Super Critical and 1 Afghan.

Probably not at all necessary.

Environment control is most important. Correct humidity (between 40 and 70%), good indoor temps (70°-85°F), good airflow, and sufficient lighting will do more for you than CO2 will right now.

CO2 is one of those things that can improve your plant health and overall yield, but only once you dial in the rest of your indoor growing environment and hit over a certain threshold in lighting. @dbrn32 may have the golden numbers. All I know is save the CO2 for later on in your grow process.

This is how I rock everything I grow. Veg at 18/6 (or 6/2 if I’m feeling brave) and then 12/12 for flower.

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I’ve had some good results with outdoor grows that I start in the tent till they can handle the weather. The autos seem to do better all year, but the photos don’t do well here in Florida in the late spring through summer, so I decided to try a full grow indoors. I have a temp./ moisture meter, an intake and charcoal filtered exhaust fans 10", an Electric Sky LED lights, in a 4x8x7.6 tent. Last batch a friend said to leave the lights on 24/7, but these were photos and outgrew the tent before could I switched to a 12/12. I did cut clones though that are doing way better than the masters, although they are smaller about 2’ or so but took them outside to do their thing.

Last fall I had a 9’ Skywalker that was awesome but highly visible to neighbors so I don’t really want them that big till things change.
Thanks again, holding off using the CO2 for this next try.


I would probably just save the cash or invest towards something else. Co2 can help your plants, but using properly can get really expensive. Some newer studies suggest it’s not as beneficial as we believed anyway.

OK thanks I’ll send it back to Amazon. Another question if I my? I’m starting to reuse the soil mixed with cocoa core and some stuff called Earth Dust along with a commercial super soil. Is that OK to do or should I start with fresh soil Fox Farms Frog top and Oceans mixed with the SS on bottom and kind of expensive. Is this a good base to start for reusing soil. Thanks for your help.