Another thing might be that you planted them in July, which has more red/orange spectrum light coming from the sun. This can make the internodes on the plant stretch (internodes being the length between stem segments/bud points). It might be like growing indoor under HPS all the way through the grow, which apparently cause longer internodes, and thus more sparsely budded plants.

Basically, you may have just missed a particular window of growing time where more blue spectrum light was being let through our atmosphere, depending on where you are growing (i am in central Cali).

But, I am no expert, so this is just a possibility. Maybe post some pics? Good luck