Big Mistake! Was running lighting 24/7!

Last night I learned that I’ve been running my lights 24 hours a day! My lights are programmed to turn off after I go to sleep and back on again before I wake up. Last night I was out late and when I came home I discovered that the lights and fan were still running. The switch on the side of the timer was pushed to the always on position…

The plant is in early veg right now. It’s a Blueberry photo. I slid the timer button to the Timer position so now they’ll receive the proper 18/6 on/off schedule.

The big question is: Will the plant enter the flowering stage???

Here’s a photo of her:

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No you need 12/12 to flower, But if there Autos they will flower when there ready no matter what light cycle your on.
you would be fine to cut back to 18/6 and be fine.
I have done this in the past and had no issues.

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I normally run 24 hours for sprouts and clones. You are fine.


You should be fine @HappyCamper. Some people run 24 hours on throughout there Veg cycle. You should be fine if it is a photo period plant I would keep an eye on it but normally it would require 12 hours of darkness to have it start to flower so I think you will be fine.


There is no harm giving regular photoperiod or autoflower cannabis 24 hours of light during the veg stage. Maybe a waste of electricity much above 18 hours of light, but it isn’t harmful. C3 plants like cannabis do not bennefit from a dark period during veg.

Happy growing,



@MacGyverStoner, @Jmesser80, @crazyots, @Myfriendis410 - Thanks for the information. I was afraid that the shortening of the light period from 24 to 18, really any drastic shortening, would trigger the flower stage…

I’ll continue the 18/6 and let this thread know if she goes into flower prematurely.

Thanks again!


Sounds good @HappyCamper. Keep us posted and let us know if you have any other questions.
Happy growing :+1:

Just be careful with that water on the leaves, may cause light burn because the water drops will work like a magnifier!


With the exception of autos, this won’t cause normal photo-period cannabis to flower prematurely. Most strains of cannabis need a minimum of about a solid 10 hours of uninterrupted darkness to flower, and some need the full 12 hours or slightly more.


@MacGyverStoner - That’s good news. Mine won’t see more than 6. :smile: