Quote Originally Posted by Opie Yutts
OK, so in your guys' humble or not so humble opinion, exactly what nanometers are needed for a proper LED array? Blue, far blue, red, far red, green, white, and yellow. I know you don't think we need the last three, but if somehow you were forced to use them in your hypothetical array, what nm exactly would you use? If cost didn't matter.
Well every color has some effect on the growth of plants. 470nm and 640nm are essentials. 420nm and 660 nm are also important, but not necessary. 730nm (IR) can be used for flowering and shorter night cycles (read my previous post about this). UV-B would also be a great addition for resin production. I have read that green and yellow colors also have photosynthetic benefits.

So I would have UV-B, 420nm, 470nm, 570nm, 615nm, 640nm, 660nm, and730nm. I would leave out white UNLESS you wanted to gain additional lumens lost by the other colors.