I agree trays don't raise the humidity that much ,but they make it easier to
maintain your plants when misting & watering + raising the humidity
slightly.I personally think it is going overboard sectioning off orchids in
the home,this can only look unsightly and will possibly lead to other
problems with pests & diseases.Especially if it is a very small space that
is being sectioned.It would need constant monitoring.
kenty
"Larry Dighera" wrote in message
...
On Mon, 29 Dec 2003 16:20:05 -0500, "Claude"
wrote in Message-Id: :

What is the best percentage of humidity to grow Phal and Paph!

I just bought an hygrometer and it shows 40% of relative humidity. Is
this
good?

Increasing the relative humidity in your indoor grow area is going to
require a whole house humidifier, or you're going to have to enclose
the grow area with some clear/translucient impervious material such as
plastic film or plexiglass. If you are using free standing shelving,
you can make a plastic sheet cover for it and put an ultrasonic fogger
inside. This amounts to an inexpensive Warden Case. Here's a link to
commercially manufactured units:

http://www.carter-and-holmes.com/cgi...or+Greenhouses

Ultrasonic foggers http://www.mainlandmart.com/foggers.html will
raise the realtive humidity in such an enclosed area to 100% very
quickly.

I find Phals grow fine in my home without suplemental humidity.
However providing a growing environment of 70% to 80% realitive
humidity seems to prevent wrinkled/pleated leaves, bud blasting, etc,
and encourage lush new growth in other genera.

"Claude" wrote in message
.. .
Thanks Ray!

My Phals are in active growing and they have all new growth of roots,
leaves
or spikes.

So therefore you're doing well, and there is no pressing need to change
anything except the size of your collection, and the size of your growing
area if it is too cramped. :-)

I did add a console humidifier in my appartement to raise the relative
humidity at first for myself, then I was just wondering about my phals.

This morning, I just misted my phals with some water and the RH went up to
60 %.
I think I will add some trays under my pots, just to give them a boost!

I wouldn't bother with them, except to catch surplus water from watering
them. That is, unless you are going to enclose your growing area. As Ray
pointed out, the effect of humidity trays is rarely measurable. The fact is
that if YOU can't measure the effect of a tray on humidity, your plants
aren't likely to either, so unless you take extra steps to reduce the loss
of moisture from the air around your plants, they won't get an extra boost
from it.

The only way you will get a measurable effect is if you create growing area
that has a small volume (such as that inside a terrarium - just take a
decent size aquarium, put a few cm of gravel in the bottom and put in enough
water to come just below the surface of the gravel. And then, with a canopy
on the aquarium, perhaps modified to accomodate a small fan to keep air
flowing (whether you recycle the air or not), you will see RH inside the
terrarium much higher than it is in the rest of the house. (yes, if you
don't recycle the air in the terrarium, you will have to add water more
frequently, but the loss of water will be controlled by the fan size and
speed, and unless you go overboard with the size and speed of the fan, the
loss of moisture from the growing area will be much slower than if you just
use a tray.)

Now, I am not saying that humidity trays can't be made to work. Rather, the
way most people end up using them will likely have no more than a 2%
improvement, and this is far smaller than the acuracy with which most people
can measure RH. This is effectively the same result that Ray described in
his report of his experiment with humidity trays. To make them work, you
have to go the extra distance to make the volume of air that the tray must
affect as small as is practicable. There is a huge difference in trying to
humidify a third of a cubic metre (the volume of a modest aquarium) and
trying to humidify 50 cubic metres (the volume of air in a modest sized
room).

The other idea I see often floated for improving RH near the orchids is to
place plenty of other plants near them. This IS a sound idea, but again,
its effectiveness will depend on the details of what you do. You have to
use plants that transpire a lot, which usually means one native to a
rainforest area and which grows rapidly (growth rate and transpiration rate
tend to be rather strongly correlated - transpiration is the combined effect
of the transport of water up the plant, primarily for the purpose of
transporting essential nutrients but also for maintaining turgour pressure,
and respiration, which produces water and CO2 as by-products, and both tend
to be high in rapidly growing tissues). I doubt you'd see a measurable
effect if you used cactus. A modest, densely planted herb garden, OTOH,
probably would have a measurable effect (depending on the herbs used). But I
could be mistaken in this, as I haven't taken the time and other resources
to do my own experiments on this.

Cheers,

Ted

"Claude" wrote in message
.. .
Thanks Ray!

My Phals are in active growing and they have all new growth of roots,
leaves
or spikes.

So therefore you're doing well, and there is no pressing need to change
anything except the size of your collection, and the size of your growing
area if it is too cramped. :-)

I did add a console humidifier in my appartement to raise the relative
humidity at first for myself, then I was just wondering about my phals.

This morning, I just misted my phals with some water and the RH went up to
60 %.
I think I will add some trays under my pots, just to give them a boost!

I wouldn't bother with them, except to catch surplus water from watering
them. That is, unless you are going to enclose your growing area. As Ray
pointed out, the effect of humidity trays is rarely measurable. The fact is
that if YOU can't measure the effect of a tray on humidity, your plants
aren't likely to either, so unless you take extra steps to reduce the loss
of moisture from the air around your plants, they won't get an extra boost
from it.

The only way you will get a measurable effect is if you create growing area
that has a small volume (such as that inside a terrarium - just take a
decent size aquarium, put a few cm of gravel in the bottom and put in enough
water to come just below the surface of the gravel. And then, with a canopy
on the aquarium, perhaps modified to accomodate a small fan to keep air
flowing (whether you recycle the air or not), you will see RH inside the
terrarium much higher than it is in the rest of the house. (yes, if you
don't recycle the air in the terrarium, you will have to add water more
frequently, but the loss of water will be controlled by the fan size and
speed, and unless you go overboard with the size and speed of the fan, the
loss of moisture from the growing area will be much slower than if you just
use a tray.)

Now, I am not saying that humidity trays can't be made to work. Rather, the
way most people end up using them will likely have no more than a 2%
improvement, and this is far smaller than the acuracy with which most people
can measure RH. This is effectively the same result that Ray described in
his report of his experiment with humidity trays. To make them work, you
have to go the extra distance to make the volume of air that the tray must
affect as small as is practicable. There is a huge difference in trying to
humidify a third of a cubic metre (the volume of a modest aquarium) and
trying to humidify 50 cubic metres (the volume of air in a modest sized
room).

The other idea I see often floated for improving RH near the orchids is to
place plenty of other plants near them. This IS a sound idea, but again,
its effectiveness will depend on the details of what you do. You have to
use plants that transpire a lot, which usually means one native to a
rainforest area and which grows rapidly (growth rate and transpiration rate
tend to be rather strongly correlated - transpiration is the combined effect
of the transport of water up the plant, primarily for the purpose of
transporting essential nutrients but also for maintaining turgour pressure,
and respiration, which produces water and CO2 as by-products, and both tend
to be high in rapidly growing tissues). I doubt you'd see a measurable
effect if you used cactus. A modest, densely planted herb garden, OTOH,
probably would have a measurable effect (depending on the herbs used). But I
could be mistaken in this, as I haven't taken the time and other resources
to do my own experiments on this.

Cheers,

Ted

Humidity trays if large enough will raise the humidity in the whole house.
Two winters ago I was still growing in the basement. I had several large
trays like those used for under washing machines filled with small stones.
I used these under the plants I was growing under HID and MH lighting. I
had several fans moving the air around the basement. I also have a
residential humidifier on the gas furnace.

In the winter when it was cold my windows in the house would fog up. I
never thought much of it then. Last winter (and so far this winter) I
haven't seen any condensation on the windows. The difference is that all
the plants have been relocated into the greenhouse. I never realized how
much water I was putting in the household air when I had the plants in the
basement.

So my point is that humidity trays must be very large to humidify the entire
closed space. In my case it was the entire house.

Good growing,
Gene

I live in Australia........paid $80K for a home 10 minutes from the centre
of a city where I work.

Climate here is admittedly different to yours.


"J Fortuna" wrote in message
...
"Bolero" wrote in message
u...
I couldn't tell you what "home" growers get because in this country most
of
us grow our plants outside and try to maintain ideal conditions.

Oh, where are you from, Bolero?

Me, I dream of someday in the future owning a house with a garden and
being
able to afford a greenhouse within commuting distance of Washington, DC
(US)
/ Northern Virginia. For now, my orchids will have to be satisfied with 4
north-facing windows supplemented by grow lamps in a rented 1.5 bedroom
apartment. And they are doing well, not ideal, but well enough to be a
great
joy in my life.

Happy New Year!
Joanna

In article ,
Ray wrote:
Sorry, but humidty trays do very little good in an open room.

Copying from my own page on humidty:

"A general caveat about all of the humidity-enhancing methods described for
in-home growing: remember that unless your growing area is sealed off from
the rest of your home, any effort to raise the humidity level around your
plants is actually trying to raise the humidity of your entire house!
Because of that, especially if there is air circulation due to fans or
forced air heating, the less active methods like the humidity trays appear
to be of very limited value."


Hmm, my orchid area is not separated from the rest of my condominium.
I think "microclimate" has to be taken into account here. Granted,
my humidity trays would be hopeless at raising the humidity of the
entire home, but locally, where the plants are actually sitting, it
is measurably better (and i have measured it).

Please note, i have also done other things to make sure that the
plants get every advantage, including replacing the windows, which
used to leak like a sieve (and in fact, this was more important at
*maintaining* humidity than anything else). Also, the plants sit
on the humidity trays themselves, my heating system uses radiators,
and i don't turn on the fans in the winter.

Humdidity trays are worthwhile, in my opinion. At the very least,
they are good drip-catchers.

--
-john

February 28 1997: Last day libraries could order catalogue cards
from the Library of Congress.