Massive cola stems

I'm going on second week of flower with my Pine Tar Kush plants. I'm not sure this is a problem but the stems at the top of my plants are fuckin huge. I swear they keep getting bigger. I'm hoping this means they are preparing for some massive colas! Most are about the size of a pencil in diameter and a couple are even bigger. The plants would be hard pressed to be 2 ft. tall and I only vegged for a month. Some one told me it's typical with kush plants. I guess I'm just kinda worried I'm going to get these massive stems in a small cola.

Guess I should add that I'm using canna aqua flora nutes along with canna boost and canna rhizotonic in a low pressure aero setup. Thanks.