do i need lights??

[rayzerh]

I am brand new at hydroponics, have been a sod buster all my life just for my family tho, nothing big. I have baught the bucket type DWC stuff and i have a south facing 12' picture window that gets sun from morning till sun down and i am setting up the buckets in that window
And when it gets warm out i will be putting them on the porch which is right outside of that window. My big question is will i need extra light???? I can buy lighting if i have to and will just put everything in another room but i would like to have everything in the natural sun if possible