HID lights for flowers/veggies
peper at med-ph.uni-sb.de
Tue Feb 6 02:41:06 EST 1996
Sodium high pressure lamps have highest efficiency of 25%.
Their spectrum is narrow, the light appears yellow.
Metal halide lamps have 22% and have a wide spectrum, the
light is the best white generated by any light source.
It appears that the spectrum is for the plant of minor
importance. Professional growers mostly use sodium because
of their efficiency.Amateurs prefer halide since they like
more the natural outlook of their plants.
In most cases 450W lamps are used. Such a lamp will
sufficiently cover 3m x 3m if 2m above ground, giving the
plants all light they need.
I use 150W lamps both in my greenhouse 3m x 4m with good
results (additional lighing), and in a 1m x 2m culture room
in the basement for very good results.For glass vitrines a
lamp 70W or 150W is great.
I experience with artificial lighting since 10 years, and
it appears that halide lamps are far superior to any other
light sources like fluorescent bulbs or "special plant"
lamps with mercury.
70W halide lamps are commercially available as indoor
illumination ( in Germany: Conrad Electronics), 450W lamps
both halide and sodium are available for commercial
greenhouses. 150W lamps can be build by yourself by
modifying cheap 500W halogen flooders.
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