Hi Potted,
I have 2 northern light auto's going now. My first, so I find it hard to recommend anything but I am glad to share what I did.
I started seed in Riot rooters + seed starting soil with a 1/3 vermiculite added, and 2 tablespoons of kind soil mixed in and I used Voodoo juice in my ph'd water, 6.3. It took about 3 days to sprout. At that time the soil around the rapid rooter was dry so I watered around the rapid rooter, and not the rapid rooter. I think after about a week in the cup the soil in the cup was drying out again, so I thought I would just transplant and water at the same time. They went into 3 gallon plastic pots and I used the Kind Soil method. Transplanted and watered with PH6.4 and a 1/2 dose of Voodoo juice and that was their final resting place.
Influenced by Green's posts, lights on 24/7, and I started to defoliate. I really only cut the big fan leafs when I saw the fan leaves starting to block out the light for the buds.
My temps ran from about 75 to 81 and rh 40 to 54%. It was slow for me to get this regulated, but at least for these Northern Lights, they really seemed to take off once the rh was around 50% and temp 79ish.
I believe they are now in their 2nd , 3rd day of flowering, I can see the buds just starting to form. I am now trying to get the temps a little lower, like 75 -77 and the rh 40-45. Lights still 24/7.
Watering with me kind of went like this: Soil on top started looking dry, waited another 2 days, then lifted the pot up for weight, stuck finger in soil, really waited for soil to get dry then soaked it and waited another 5 to 7 days before checking.
I'm guessing another 2 -3 weeks. Everything looks healthy, so far.
Last time I grew stuff was early 70's outside, last time I smoked was over 30 years. I will be happy to get anything, even if the died today, the leaves, stems, and partial buds are getting smoked tomorrow LOL
I hope any of this helps!