im not 100% positive, but scrogging starts in veg. a lot of people seem to go different routes after veg. some people seem to continue to tuck the stems and filling out the screen until the stretch is totally finished (about 14 days after 12/12). i feel that puts too much energy in the wrong place at the wrong time, imo. Personally, I think the screen should be mostly filled by the flower stage. my first scrog attempt wasn't the best, and im still learning myself about the technique. my main thing is remembering to put it over the vegging plants early on enough. i tend to let my plants get away from me, and by the time the scrog net is added, ive wasted a lot of time and energy growing vertically when that is never my intention with a scrog grow. sorry for the rant ha...had some sativa for dinner