Light requirements (do I need a light meter?)

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Light requirements (do I need a light meter?)

Post by k barret » Mon, 03 Jan 2000 04:00:00

The answer for me was yes. The light meter was the second item I bought,
after Rebecca Northen's book. I have found it almost irreplaceable as a
training tool. Many times authors will talk about growing something in
'Cattleya' light or some such blather. Well, what the heck is that
supposed to be when its at home??? And the trick about using your SLR
camera is just too weird, for me anyway. So the meter was/is a great
tool. Its the only way to be sure what you're 'getting'. Of course I had
to go overboard and buy a real nice one, but really, any meter will do.

I've often wondered if a meter that would quantify the color of light
might be helpful too, since plants photosynthesize in one color, bud in
another and find green to be a total waste of wavelength. *G* That would
have been helpful when I was growing under lights. Just to check on the
manufacturer's claims. Maybe help in determining when to re-lamp. Just a

Any relation to the book 'Death and Life of Bobby Z'? [Just kidding]

K barrett


> I'm just starting to grow orchids, and am unsure about how much light
> I get in my S-SW facing window.  It gets partially (about 2/3 of the
> day) shaded by a tree during the summer, and has a screen on it
> (removable).

> Will there be enough light for Cats in this window?  Phals (maybe with
> blinds partially closed)?

> Would it be worth it to invest in an inexpensive light meter (one of
> the $30 cheapies like this
> ) to
> see what I'm really getting inside the window?


Light requirements (do I need a light meter?)

Post by Liz D » Wed, 05 Jan 2000 04:00:00

>I'm just starting to grow orchids, and am unsure about how much light
>I get in my S-SW facing window.

What latitude / location are you?

I am at 40 N and have a south window.  In winter when the sun is out, I
believe I have plenty of light for catts, but since it is cloudy 2/3 of
the time in winter I bought a light fixture.  If there are orchid growers
in your area you could ask them what they do in their greenhouses to get a
feel for the light conditions there.

Liz Day
Indianapolis, Indiana, central USA, 40 north latitude, USDA zone 5b.


Light requirements (do I need a light meter?)

Post by Christopher Allen Schult » Fri, 07 Jan 2000 04:00:00

I have an Oncidium divaricatum which I recently bought at an Orchid
Society auction 2 months ago.  This plant has flowered (before I got it)
and is appearently 4 years old (either that or it was remounted 4 years
ago).  It is mounted on a Tree Fern slab, it is*** on the south
facing wall 12 feet from a south facing window.  I live in WI.  Shortly
after I got it one leaf turned yellow and broke off above the base,
recently I found what looked like a healthy leaf on the floor and another
leaf turned yellow and fell off today.  The leaves which are falling off
are paddle shaped and originate from a small node, there are still six
leaves like this on the plant.  There are also two leaves which look like
knives originating without nodes from behind the root mass these look
healthy.  I water this plant by spraying it every day.  So, why are my
leaves turning yellow and falling off?  Is this normal winter behavior?
Does this plant need more light?