Thats a debate ive read on here many times. I run my lights 24/0 For the entire veg if i grow a Photoperiod then when you want to flower it i like to start 2 weeks early, ill flip the lights to 18/6 for 1 week to help the flowering hormones build up, then i throw it into 12/12. If im growing an Autoflower i run my lights 24/0 the WHOLE time . Cause autoflowers flower on their own
Personally I like to run 20/4. A little bit of darkness from my experience helps with root growth. I have run both light schedules for veg and had success with both. But 20/4 seemed to work the best imo I agree with dark tho. If u do veg 24/0 do the 18/6 a week before flowering. This for photos. Never grown autos.
I run 24/0 in the winter to take advantage of the heat. In the summer i do the opposite and run 18/6 to help fight the heat. The difference if any, is so small and unnoticeable that its not a concern too me.
I take my inspiration from mother nature IMO, outdoors light and seasons is genetically imprinted, even though we grow indoors I try to stay within reasonable parameters of that, keeping in mind that although spring planting is typically Apr/May and harvested in late November. Our girls don't need to veg that long. So, I plant seeds in late August and harvest in late November, which is our cold months, which helps buds to fatten; combined with shorter days this sinks with cannabis' life cycle. No telling when clones were veged, so any time Seedlings: I do 20/4 for ~ 7 days then drop to 18/6 for ~ 2 weeks, then ~ 14/10. When growing sats I may wait until I see pistils, then 12/12 until ~ 3 weeks to harvest, then 11:45. I know that doesn't seem like much, but it is for sats