Evening, all.
I am actually taking a college course in remote sensing, and among my reading assignments was the this webpage, which has been made into a PDF for my course:
Light and Plants
It talks about light that plants need, in what wavelengths, PAR values of each type of light, etc. It is very simple to understand and doesn't get too technical (which is good if you're like me and tend to get lost in technical speak when trying to research this topic).
So I thought I'd share it here for people who are just beginning to research light and keeping plants under lights/supplementing light over the winter.