Plants do most of their stretching during the dark cycle so I don't think less light hours would help too much. WHIPPEDMEAT is onto it. Cooler temperatures combined with metal halide lighting will give you the slower growth and short internodes you are after.Anyone have experience with interrupted light cycles to stay in veg?
Bonzai is interesting too. I should look into that.
One of my problems is that they get too big and end up getting chopped to start over. If its possible to save some electricity with an interrupted light cycle that would be cool too.