Hi Folks;
        I'm a newbie on the net so please forgive me if I screw up. I've
been lurking for over a month now reading the plant list with great
interest. I've been growing plants for over 20 years with good success. I've
monitored with interest the discussion on lights and plant growth. Everyone
seems to place a great deal of importance on the type of lights used. My
question for the learned folks out there is "why?"
        This may seem like a stupid question but if you use a combination of
fluorescent and incandescent light, have you not covered the greatest part
of the visible light spectrum. It is my understanding that chlorophyll
absorbs blue and red light best at 450 nm and 675 nm respectively.
        Chlorophyll, however, is not the only light capturing molecule.
There are also carotenoids which absorb blue and green light ( at about 500
nm peak ) as well as phycocyanins which absorb green and yellow light ( at
about 600 nm peak )
        To me it would seem that the production of ATP and NADPH would
occur, for the most part, across the entire spectrum of visible light. Could
not any deficiency be made up by increasing the intensity and/or the
duration of the light that one uses ?
        This question has actually puzzled me for quite some time now and an
answer would be personally most satisfying.
        Jim Robinson   jim at cka_org