Vegitation Lamp During Flowering

well, the difference is the temperature color.. veg-lights have more of a blue spectrum, as this will keep the plants a bit shorter and will produce tighter internode spaces (which is what you want during vegging), while the red spectrum will help more during flowering times and provide better results.. In 2009 i have tested with various plants (mostly hot peppers) under T8 lights and i had 3 setups: one with pure 6500K lights, one with pure 3000K light color and one mixed. When i started them under pure 6500K they were really short, but extremely bushy with a lot of branching. The plants were mostly growing sideways instead of upwards. The other set under pure 3000K made them stretch much more during veg (which i didn't like either). To me the best was a mix of both, but more leaning towards the blue-ish side for veg. This still kept them rather compact, but not overly. Given that cannabis goes through the stretching phase during flowering, I'd actually like the more compact start. For flowering the red did make a big difference in the end-result. I removed almost all of my 6500K CFL's and not only did the peppers start fruiting much better, there were almost no flower-drops (hot peppers drop their flowers if they don't start to fruit), which was regularly happening under blue. I understand that this isn't that applicable to cannabis, but i never wanted to waste a nice cannabis plant for that test, by just keeping her under a (mostly) blue light. Also don't forget, that by limiting your yield, your price-per-gram goes up much higher, because the 600w does draw quite some power. Each of my light-setups was drawing around 90W at the wall, so I asked myself "why then limit yourself unnecessarily"? Today i always go for "full spectrum white" with preferably 3500K color temperature (that's what my cxb3590 COB has, as well as my two quantum boards.. the 3 additional quantum boards i have already ordered, are also at 3500K.. only the one 36w screw-in-LED has 4K i believe, but there 3500K was no option).. this way i have the full spectrum equally balanced and get some blue for veg, as well as red for flowering in..