"Vox Humana" writes in article dated Sat, 07 Aug 2004 16:08:44 GMT:

"Popcorn Lover" wrote in message
. 13...
I have a gloxinia, a hydrangea and a few other indoor plants on a plant
shelf
in the living room. I've been using a fixture with dual 40 watt Gro-lights
over them for years now, but it's not real great for getting some of the
plants that require more full sun, to bloom.

What other kinds of lights are available, that won't bust the budget or
use
massive amounts of energy, but will simulate direct bright sunlight
better?

The problem with your request is that sunlight *is* much more intense than
any normal indoor light. You could up the ante to 8 bulbs instead of 2.
There are other fluorescent alternatives to Gro-lite bulbs, some may look to
the human eye to be more like sunlight but I doubt the plants would grow any
better.

I've heard of people growing plants under mercury vapor or high pressure
sodium lights -- the kind of things used for streetlights or security lights
outdoors.

I have read that Gro-Lights aren't any better than standard fluorescent
bulbs. Maybe you just need a fixture with more bulbs (or higher output)
that is closer to the plants. The amount of energy received by the plants
is inverse to the square of the distance to the source.

That's true when your light comes from a single point, but if it comes from
a 4' tube and you're already closer than 4', intensity varies inversely more
like with the distance, not the square.

Moving the fixture
closer to the plants will significantly increase the amount of light energy
they receive.

Yes, with fluorescents you can put the lights right on top of the plants.
Not touching, because contact would interfere with aspiration.

-- spud_demon -at- thundermaker.net
The above may not (yet) represent the opinions of my employer.