permaculture

["Lawrence F. London, Jr." <lflj@intrex.net>]

And there are LED grow lights.

-------- Original Message --------
Subject: Re: [SANET-MG] Grow lights
Date: Wed, 21 Nov 2007 00:08:12 -0800
From: Misha Gale-Sinex <mgs2369@COMCAST.NET>
To: SANET-MG@LISTS.IFAS.UFL.EDU

Howdy, all--

Tim asked about "grow lights" and Kathryn replied regarding
"fluorescent lights."

Remember that "fluorescent" isn't a term that tells us much about the
light spectrum the bulb emits.

It means a tube filled with gas that glows by having the tube's
cathodes energized by a ballast. That is, fluorescing. Technically,
neon (and argon, etc.) lighting is fluorescent.

You wouldn't expect your plants to thrive on a black light, and it'd
be cruel to expose your tropical fish to, say, a regular office
ceiling fixture bulb. They all fluoresce--like full-spectrum lights
and proper fish-tank lights--but differently.

And different quality fluorescent lighting has different effects on
plant growth, because plants like light in the infrared and UV bands
of the natural light spectrum. Conventional fluorescent bulbs' light
is shifted to the blue end of the spectrum.

Here's a very cool site by a citizen that does the best job I've seen
of laying that out in the context of plant-growing:
http://www.waynesthisandthat.com/fluorescent.html

I dug around awhile before my poor brain remembered where I'd seen
this spiffy article on artificial lighting for plants. It's from the
fine folks at Gardener's Supply in Burlington:
http://www.gardeners.com/Gardening-Under-Lights/default/5080.page

See this explanation from Virginia Tech's "How Things Work" site:
http://howthingswork.virginia.edu/page1.php?QNum=1462

Be careful with those things, by the way--ballasts, I mean. Be
careful where you locate them. They generate powerful electromagnetic
fields. Just today my telcom engineer husband was "fixing" a phone
problem by convincing the caller to move their fluorescent desk lamp
away from their handset...and their head.

This teaching activity from the StarDate Web site will show you how
you can conduct a simple spectrum analysis of lights you want to use
for your green buddies:
http://stardate.org/teachers/activities/spectroscope.html

peace
mish