It depends on how powerful the bulbs are. I use a 125w blue for propagating, a 2x250w blue for rooting (fresh out of propagator) and a 400w sunmaster for vegging. The sunmaster has both spectrums so most of the red spectrum is wasted but it covers a bigger surface area so is better when your plants are in bigger pots. There are a few companies making l.e.d grow lights now though, they come in red, blue or mixed spectrums, have the benefit of cfl,s (low power consumption/ heat output) but can be used all the way through both cycles.