LST

As long as you notice that the growth is increasingly distributed to the un-topped shoots and these have caught up in height with the apical shoot. How long it takes always depends on the genetics, so on the pheno; even if all three seeds are the same strain, they react differently to the training. The condition of the plant certainly plays a role too; if they were stressed beforehand, it probably takes a bit longer. The best results come when you combine LST with topping/fimming, as this can lead to a uniform surface that optimally utilizes the light; this is all referred to as mainlining.