First time growing

Hey guys. This is my first shot at growing, i have two plants on the go and this is one seems to be slightly behind the other/ over crowding himself. I am using a super soil with organic nutrients, so there is not a lot i can change but is there anything i can do to try keep him from over crowding his under layer of leafs ? I have been low stress flexing his under layers down trying to get them to reach for some light (using a 1500w LED). His bottom set of leafs have started to curl under from lack of light.