previous posts, ditto...and...
what do... >you< ...want to do?
what's your climate/environment like? (So. Calif. vs. Mass. means adjusting your goals)
if i were making the decisions for you i'd let 5 re-veg'ers go on their own & harvest the other 5 for early smoke. the 5 budders might even start to catch up but not very likely. also remove all the bud from the 5 that are revegging because it'll just get funky by the end of the season. just eat the bud like f'n animal if it's not worthy of much...it'll be a bit funky but you'll like the effect.
you can remove a lot of material on the re-veg plants safely like 2/3...i know it'll feel terrible but it should trigger growth response. try experimenting since you're learning & not feeding your kids with it hehe and do 1 different change to each maybe? leave a "control" plant?
sorr if the answers aren't all numbered but here we go...
the "singlet" leaves & 3-finger leaves etc... all show up when the plant transitions back to veg. if you've seen a seed sprout, the first sets of leaves are also singles. i dunno if there's a connection or not. you're experiencing what i was doing a few years ago... very frustrating lesson. do you know why it happened? because they went from (probably) 24hr light to something like 14/10(dark) and that's pretty abrupt. if they had been "conditioned" by easing them a half or an hour a day to get kinda close to your natural light/dark period. read up on cannabis & light period(aka photoperiod).
i wouldn't transplant, especially since fabric pot transplants are not gentle to the roots. you can get decent 1/2 lb. in a 15 gal. still i think. ?? OGers?
don't bother with the nutrients for reveg now-- it looks like you've got a soil mix ?? i wouldn't bother feeding the bloomers either, just water & harvest.
OGers-- notice how closely they resemble auto-flowering plants??...crazy.
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