From previous research I found plants need ....and the sun gives

5.3% red light 723.18 nanometers
36.3% blue light 508.7 nanometers
58.3% yellow light 616 nanometers

So in Hz that would be

401.78 Hz at 5.3%
669.9 Hz at 36.3%
508.7 Hz at 58.3%

I do not know how to put that as a wave file but I can almost guaranty results