Athosanswered grow question 6 years ago If we are talking about an auto strain, then the window of oportunity to TOP is very narrow, after the 4th node, why? because after the 5th pair of leaves fully opens, then flowering starts. The time to TOP a regular strain depends on how many plants per sq ft you are going to grow; I would suggest trying to get between 8 to 16 tops per sq ft, that would mean TOPing above the 4th node at the very earliest or the 8th node; LST should start as soon as the stems are long enough to tying them down. HST, I assume you mean supper cropping I use as a mean when some TOP (usually the main one) needs their height be brought under control and is not responding well to LST. The best tip for a good yield would be to use all 3 trainings to keep a canopy as even as possible so all tops are at the same height; get the lights as close as possible while keeping th eheat in check; have a good wet / dry cycle (4 to 5 days is what I aim for my waterings to last).