Re: Re: Light tubes

Joachim Nerz (
Wed, 1 Feb 1995 18:48:57 +0100 (MEZ)

On Wed, 1 Feb 1995, dave evans wrote:

> > From: Joachim Nerz <joachim.nerz@STUDENT.UNI-TUEBINGEN.DE>
> > I think, the easiest and cheapest way to grow CP's under lights are the
> > simple Industrial cold-white tubes, you do not need the expensive
> > Growlux-lights; very bad experience I had with the blue-red
> > 'fluora'-plant-lights!
> >
> > Bye
> > Joe N.
> Could you please elaborate on your very bad experience? I am thinking
> (huh-oh) of building a grow area using some of GE's 33 watt Sho & Gro
> Bright Stik bulbs; just to try something new. I took a horticultural
> class last year and we were taught that plants mostly use the reds and
> blues of the spectrum with near complete disregard for greens and
> yellows. Is this on the money? If true wouldn't a bulb that produces
> more reds and blues be more cost effective at least a far as electrical
> consumption is concerned (more of the electricity is in effect used by
> the plants)?
> Thanks, Dave Evans
Hello Evans,

my bad is not the experience of money (they cost 5 times more than my
white ones), but with the quality of plants, which I have grown under
this lights. When I used this violet 'plant-lights', plants suffered,
were green and were oftenly victims of fungi. It is right, theoretically,
this violet tubes have a spectrum with 5 times more red and white than
the white one (you are right, just the spectrum, which plants like for
photosynthesis), but it seems, that first, you have to tell it your
plants :-). With the usual white ones, anyway I had much better success
and that's also the experience of several other growers, which I know.
Why they are growing better, (physics, spectrum ...), maybe somebody else
can tell you!


Joe N.