Timothy wrote:

On Fri, 04 Jul 2003 17:19:18 +0000, Joseph Meehan wrote:

Well maybe not near complete spectrum, but better and may well
be
good enough. It depends on the plants and the stage of their
development.

Red light is generaly assoiciated with flowering and blue light is
generally assoiciated vegetative growth.

For starting plants, it follows that we can skip the red band.

This can be seen in nature with
spring light (more blue) and summer light (more red). Your not really ever
going to get true 'full spectrum' from any light source, be it
fluorescent, hps or mh. Some get rather close (grow-lux and ag-grows), but
no affordable light source will replicate the suns spectrum. The only
light which is almost near sun spectrum is the sulphur type bulbs and the
led lights. The sulphur bulbs are not ready for market (if they ever will
be) and are increadibly expensive to make. The led lights are very new and
expensive for the general consumer. They could turn out to be only as good
as the fluorescents as far as total lummen out put and intensity, but I
can't afford one to find out.

Some reading material on sulphur lights...
http://www.thekrib.com/Lights/sulphur.html

And even closer to sunlight is actual sunlight. Set the plants out, or
place them beneath a skylight. Install a sun tracking mirror over the
skylight if you have money to burn.