Mint Jelly and purple haze in 2x2

welp, still learning and growing here as a new grower. First off, I need to either a) identify some strains that are short or b) figure out how to switch photoperiod strains to flowering early so that they don't get too big. I decided to preemptively top off the tallest cola from the PH. it was 8" taller than all the others you see in the photo and was too thick to try bending down with some low stress training.