you CAN veg with those, but 6500k is best. if you aren't short on cash, pick up a double 48" flourecent fixture (about ten bucks) and two ge daylight tubes (lowes, 6500k, 3050 lum ea) these bulbs are "cool". the plants can litterally touch the bulb with no burning at all. this fix will get your three plants all the way through veg. you'll end up swearing by flouro's, lol

kp