Quote Originally Posted by BLaQLiGhT
Halogens give off white light that are blue and purple on the light spectrum. Plants need orange, yellows and red light spectrum. HPS lights are the best but Mercury vapor lights or Metal halide lights and Compact flows work too..
Actually mercury (Hg) lights are no good either.


Plants need more in the blue for veg (metal halide) and more in the red for flower (Sodium).

Read up on the appropriate flourescent types that approximate these wavelengths.

Halogen, incandescent (even plant lights), uv (black) lights, heat lamps, propane lanterns (yes it has been suggested on this forum), and mercury vapor lights are not useful to plants. You want something in the right range that does not emit too much heat or use too much juice. The only promising new technology is LEDs just because you can really tweak the wavelength by adding different types to your growing array.

Why reinvent the wheel?