Hello, all,

I just got some light fixtures to supplement the light for my orchids
that are in a west window. At Home Depot I was sold some lights that
they said were wide spectrum. Well, the guy didn't seem to understand
what I wanted, after all. They are apparently considered intermediate
spectrum: the color temp is 3500k.

This seems to be pretty close to the temp for bulbs rated as warm. If
I mix two of the 3500k bulbs with bulbs that are rated cool, will I
have enough of the spectrum covered? Or do I need to ditch the 3500k
for 3000k? This seems to be a bit hard: there don't seem to be any
"warm" T8 bulbs on the shelves.

I'm no pro here, but the color temp and spectrum aren't necessarily tied
that closely. I use the GE Sunlight and Sylvania Sunstick bulbs, which are
great, and they're rated at 5000K.

If you can get somebody to order from Grainger for you - they don't sell to
individuals - they have a Rapid Start T8 from GE, the Chroma 50 (Sunlight
bulb). It's item 5V572. It's a 36", 30-watt bulb, 1.5" diameter. You
didn't mention if you have that or the 1", 25W need, or 4', 32W size.

--

Ray Barkalow - First Rays Orchids - www.firstrays.com
Plants, Supplies, Books, Artwork, and Lots of Free Info!

.. . . . . . . . . . .
"Bette Noir" wrote in message
m...
Hello, all,

I just got some light fixtures to supplement the light for my orchids
that are in a west window. At Home Depot I was sold some lights that
they said were wide spectrum. Well, the guy didn't seem to understand
what I wanted, after all. They are apparently considered intermediate
spectrum: the color temp is 3500k.

This seems to be pretty close to the temp for bulbs rated as warm. If
I mix two of the 3500k bulbs with bulbs that are rated cool, will I
have enough of the spectrum covered? Or do I need to ditch the 3500k
for 3000k? This seems to be a bit hard: there don't seem to be any
"warm" T8 bulbs on the shelves.

"Ray" wrote in message ...
I'm no pro here, but the color temp and spectrum aren't necessarily tied
that closely. I use the GE Sunlight and Sylvania Sunstick bulbs, which are
great, and they're rated at 5000K.

If you can get somebody to order from Grainger for you - they don't sell to
individuals - they have a Rapid Start T8 from GE, the Chroma 50 (Sunlight
bulb). It's item 5V572. It's a 36", 30-watt bulb, 1.5" diameter. You
didn't mention if you have that or the 1", 25W need, or 4', 32W size.

--

Thanks for the info. The fixture I got is the 4', 32W size. Since
no one here knows me, I don't expect anyone to do that sort of thing
for me. I may get a different fixture (T12, 40, I think) that I know
I can get GE full spectrum bulbs for.

You didn't say what kind of fixtures you bought so I'm assuming they're
for fluorescent tubes. If you have just (incandescent) lights in the
3000k - 3500k range you're missing an important part of the spectrum.

Look for "GroLux" tubes, which are designed for growing plants. I've seen
them at Home Depot and other hardware stores. Also stocked by many
nursery's. The configuration I've seen recommends a combination of the
GroLux tubes and some incandescent light bulbs. I've seen books about
growing plants under lights but I don't have any. Suggest you look at a
book store for one.

I'm not sure how color temperature applies to lighting for plants. My
experience with color temperature applies to photography and scientific
use. "Standard" color film is designed for "daylight" light, which is
about 6000k. (I don't remember the exact numbers so please don't beat me
up if I'm off a little). "Regular" tungsten light bulbs are in the 3000k
range. It's missing the blue light that's in daylight. That's why a
picture taken indoors without a flash has an orangish cast to it. All
bets are off with fluorescent lights because the light comes from the
glowing phosphor that coats the inside of the tube.

I'm planning to setup some lights so I'll post any info I find.

Hal Tess

Hal Tess AT Hot Mail DOT Com (Delete the spaces and fix the words in
caps)



Bette Noir wrote:

Hello, all,

I just got some light fixtures to supplement the light for my orchids
that are in a west window. At Home Depot I was sold some lights that
they said were wide spectrum. Well, the guy didn't seem to understand
what I wanted, after all. They are apparently considered intermediate
spectrum: the color temp is 3500k.

This seems to be pretty close to the temp for bulbs rated as warm. If
I mix two of the 3500k bulbs with bulbs that are rated cool, will I
have enough of the spectrum covered? Or do I need to ditch the 3500k
for 3000k? This seems to be a bit hard: there don't seem to be any
"warm" T8 bulbs on the shelves.

Visit the URL below for a nice writeup. I copied this paragraph from the
page.

It is important to select artificial lighting that provides both ends of
the spectrum in sufficient intensity. Household
incandescent bulbs are very heavy on the red end, while cool white
fluorescents are weak in reds and strong in the
blue end. That's why 50/50 wattages of each can be combined for
successful growing. Recent developments in
fluorescent phosphors have yielded spectra more like natural sunlight by
boosting the red end of their light output.

http://www.firstrays.com/plants_and_light.htm

Hal


Bette Noir wrote:

Hello, all,

I just got some light fixtures to supplement the light for my orchids
that are in a west window. At Home Depot I was sold some lights that
they said were wide spectrum. Well, the guy didn't seem to understand
what I wanted, after all. They are apparently considered intermediate
spectrum: the color temp is 3500k.

This seems to be pretty close to the temp for bulbs rated as warm. If
I mix two of the 3500k bulbs with bulbs that are rated cool, will I
have enough of the spectrum covered? Or do I need to ditch the 3500k
for 3000k? This seems to be a bit hard: there don't seem to be any
"warm" T8 bulbs on the shelves.