I live at almost exact same latitude as jrgower (hi and welcome btw - I'm in Toronto) and we are still getting well over 13 hours now on Sept 1.
But jrgrowin is right. 12-12 is just the accepted standard for indoor growers to be guaranteed enough dark time. It's strain dependant and though I dont grow indoors, I would guess that 13-11 or even 14-10 would work for a lot of strains.
It's also because the light outdoors can mimick darkness to the plant by including high amounts of the far-red spectrum of light around sunset and sunrise. The far-red light extends the dark period because the plant's phytochromes can't "see" far red light in a sense. So 13 hours of outdoor light might be the same as 12 hours of indoor*
*Disclaimer: everything I just wrote is based only on my memory which is historically unreliable and could potentially contain absurdly false information
But welcome to the site jrgrowin and from what you said, it sounds like you're all set to have plenty of good smoke. Don't get too caught up in the volumes and volumes of discussions on things like what are the best NPK ratios and calmag requirements for an indica dominant hybrid from feminized seeds and grown in coir in 2000 gallon smart pots using etc etc etc. Don't get me wrong, theres a shit-tonne of good info on here, but it's too easy to get caught up in a lot of hype and forget about basic plant needs.
Sounds like your plants roots must be pretty tight in those containers. Mine is in about a ten gallon and same situation. I'll put a pic in below. I would suggest that if yours are like mine, you will need to be watering every day. When they are super root bound, the soil dries up real quick. The nutrients arent held in much either so a slight bit more feeding could be necessary.
I'd love to see pics of yours
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