I had questioned tht myself..was doing research and came across the "farmers almanac." This thing is the shit!! Tells u how many hours of sun your specific climate zone will receive, at any-given time. If you wanna know how many hours/vs darkness on May 15th..the almanac will tell you. those starting indoors an thn transitioning to outdoor can simulate your veg light to match what the hours will be when u are putting ur girl outside. So if you plan to put her outside on May 15th..an on this certain day the lighting outside..is 14/7 thn you would want to veg on 14/7. Now when you plant it, it will be receiving the same amount of light outdoors as it has been inside. Gorilla's got ths figured out lol