T5 2 foot bulbs

Hey i got a question,as some of you know that have answered my many questions i am playing with some dwarfs in my windowsill and i have a 2ft flo. mounted in the laundry room window which is only like a 2.6x2'6 frame.Anyway i see where i can buy a t5 to go in the fixture and one is a cool 6500(degree symbol)k and the other a warm 3000(degree sym)k,which is the bulb i need to just let them stay in the window from seedling to fully mature?