Looking pretty good man, the thing about auto flowers is any stress that happens will cut your yield / potency drastically. Go very easy on the nutes, especially at the start. But I guess you learned that one the hard way eh? Regretfully I think we al do
It's a learning experience, as long as you learn something, and maybe get some smoke to go with it, I figure it's all good. I have a few questions for ya and maybe I can help out abit.
How many times did you repot? Were they root bound when you transplanted? They are touchy about being transplanted.
I personally start my seeds in the smallest pot you can find not sure the size but like 4oz or 2"x2", then after 10-14 days I move them into large pots, some may say its overkill but I use Roots #5(gal) 16Liter pot smart pots.(They look to be twice as big as yours) But I don't believe the tags, I think they hold about 3.5gal each maybe someone knows better?
What lighting schedule are you using? I leave my lights on 24/7, but with some genetics you might have to change it to 18/6, or maybe even 12/12 to get them to start flowering. I see you have slight pre-flowers but you should have more, it could be from the nute burn tho, and possibly repotting issues.
What nutes are you using? The tips of your leaves are turning down a bit, a sign of N toxicity. Too much N can delay flowering.. Have you used any bloom nutes yet? When I see pre-flowers appear I add a small amount of bloom nutes, like 1/8 strenght ontop of the grow im using. It's a fine line tho, if you use too much grow (Nitrogen) you can delay flowering, but if you stop the grow too soon, before they are done their stretch they will stay smaller and flower sooner.
Here is a pic of my tent full of auto's at day 43. I can grow monsters in veg, and pre-flower but run into problems during late flowering, im still learning for sure...
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