my plants are 6 weeks old and their both around 20 inches tall, the thing is that they dont really have many branches comming off of them, when are they gonna start getting all bushy and more full
they should be getting there...especially when you start flowering. It also depends alot on the lighting u have, a high power HPS will make a plant much bushier than a few fluoros.
it sounds as if ur plants are plenty tall enough, so try what i did (it really works!!!) see the tip at the top of the plant? pluck it off 2 about 1 inch down the stem. ur plant will not grow any taller, but will put alot more energy and resin into growing the flowers at the internodes of the plant. therfore making the plant more bushy and more potent!!!! (p.s try it with 1 plant and see how you like the results be 4 doin it 2 all of them.)