Best wavelengths for photosynthesis:
Chlorophyll A: 435 - 665 nm
Chlorophyll B: 490 - 650 nm
I'm interested to hear as well.
As an experiment, Ive ordered a KZ Fiji Purple for its red spectrum. Its the only bulb I can find which would satisfy a plants chlorophyll A
spectral needs in red @ at 650nm. The blue end of the spectrum seems to me much easier to find and satisfy.