well my friend is using a 400 watt hps for vegging 10 black dominas right now and there bushy as ive ever seen that strain so yes you can veg with hps go to hightimes they have some good answers also and all those people are pros at growing gardens indoor and outdoor that were i got my info for a small outdoor garden i did year or two ago i should mention the space he is using is 8 square feet and 6 foot tall and his plants like i said are good and growing viguoresly ill try and putt up some pics if he doesnt mind