longer dark period=longer internodal spacing?

longer dark period=longer internodal spacing?

Obviously nodes stretch in flowering with the 12/12, but would 20/4 make plants grow shorter and bushier whereas 18/6 or maybe 16/8 cause plants to grow a little taller?

i wonder that myself..i'm doing 22/2 just to give it a little rest..

All the growers I've discussed this with seem to think the difference between 24/0 and 18/6 isn't enough to make the extra light worthwhile.

yes. during the first two weeks of growth i use 24/0, my plants have limited spacing in between sets of leaves. I then switch to 20/4 for a week, then 18/6 for 2 weeks. That sets up good spacing for flowering. I usually get a lot of bud in a limited amount of height.