TZ -OH6
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Re: Phalaenopsis Help!!!!

I'll just put in a few pennies here.

Neither misting nor humidity trays make a difference in humidity around a plant in an open room. You can test it with a hygrometer. The physics are against it. Evaporation cools air, and cool vapor filled air sinks. Then the water vapor disperses through out the room. So to help the plant with high humidity you need a cool mist or steam evaporator and your wall paper will mildew and peel off.

The easiest way I have found to maintain turgid leaves for orchids in a home environment is with single pot hydroponics using an inert medium (sometimes called semihydroponics).


If the lowest leaf yellows and dies off as the new leaf is growing don't worry about it. It is natural translocation of nutrients common in less than perfect conditions. In nature, Phals rarely have more than two or three leaves. You will get a flush of new roots after that leaf matures.

imafan26
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Re: Phalaenopsis Help!!!!

Actually, it is true if you live in a cold or hot dry climate. It is also true if the plant was in an air conditioned room 24/7. Air conditioning takes the humidity out of the air and plants dry faster. The humidity tray should still be able to help the immediate area around the plant, it won't be enough to humidify a room. That is why people in drier climates mist their plants often.

Greg said he lived in a hot, humid climate. So do I, humidity is indoors and out. The average humidity here is 80%. I don't have air conditioning. Air conditioning and a sealed building reduces but does not eliminate humidity altogether unless the plant is positioned right under a vent.
Happy gardening in Hawaii. Gardens are where people grow.

TZ -OH6
Super Green Thumb
Posts: 2097
Joined: Fri Jul 25, 2008 11:27 pm
Location: Mid Ohio

Re: Phalaenopsis Help!!!!

It doesn't change the physics of it. You can test it (I have) with a hygrometer placed at different heights above a humidity tray in a perfectly still room. I cheated and used high wicking hydroponics pebbles instead of gravel and I still didn't see any change in humidity at heights anywhere near the potted plant. At room temperature water evaporates slowly, cooler air sinks in warmer air, and vapor laden air is heavier than dry air. Most rooms have enough imperceptible convection currents to move vapor far from the source quickly, which can be tested with perfume or vinegar.


Wet gravel bottomed terrariums with any kind of vented top also lose significant amounts of humidity when the fans and lights are on. But once the fans and lights are off the humidity rises fairly quickly.


Hand misting is mostly good for roots on mounted or bare root plants, unless you are talking about the cloud forest stuff. Otherwise it is neutral or bad as it can get water in the leaf axils which can lead to crown/axil rot.


Phals also have CAM photosynthsis like cacti, agave and aloes (most orchids use the normal C-3 or high temp C-4 pathways) so that should tell you how much Phals care about high humidity.

They do like temps around 80-85F much more than they like temps in the mid to low 70s and below.

imafan26
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Re: Phalaenopsis Help!!!!

I actually haven't really needed to test humidity. My test is my nose. Whenever I am in a dry climate I get nosebleeds. Rarely happens at home. In a dry climate it may be very hot but very little sweat. In a humid climate lots of sweat as the body tries to cool off by giving off water.

My normal air in and out of the house is very humid. Right now it is 6 p.m. and my humidity is 83% and the temperature is 73 degrees. Thank goodness for trade winds without them it would feel more like 80. When it is cold here (for me that is anything below 70), if it rains on the ground and it dries up, I won't see anything. But if it rains a little and the sun comes out and it is 88 degrees outside. I will see the steam rising from the road. The road will be too hot to comfortably walk on barefoot so it is much hotter than the air. I think it the water vapor is probably rising at the cooler temperatures. It probably does it slower, since the road takes longer to dry, and even though I don't see the steam, the water had to go somewhere. It might be difficult to measure humidity if there isn't much difference in temperature of the substrate holding the water and the air.

As for humidity trays, I don't really need them. I have plenty of humidity for the plants and I only keep plants in the house for very brief periods, they are much happier outside where they get more light and air. I also can get lazy if there is a saucer under a pot so it forces me to take the plant to the sink to water and drain them. There is less chance then of wicking water from the tray and rotting the roots. But in a drier climate the humidity trays can't really hurt.
Happy gardening in Hawaii. Gardens are where people grow.

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applestar
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Location: Zone 6, NJ (3/M)4/E ~ 10/M

Re: Phalaenopsis Help!!!!

I guess both of you are confirming the reason I find mine blooms better if I vacation them outside, and why one year when there was a severe drought enough to cause ground to crack, they actually did not fare well. And why this year with weekly rain enough not to need to water the garden beds, they are doing fine up on the picnic bench instead of on the ground in the shade garden. -- very humid and muggy this year.

During July, I kept thinking it was getting too hot and maybe I should bring them inside, but they just looked happy, even when other container plants were flagging and needing daily watering.

I think too I need to review my timing to bring them back inside and make sure to do so before it gets too cool. (though I'm puzzling over the forecast this week that it's supposed to get down in the mid-50's -- in the middle of August??? -- will it hurt them to stay out for the couple of nights?)

-- just re-checked forecast !!! it's supposed to get down to 52°F tonight !!! :? --

This past winter, due to space constraints more than anything else, I put my phals (and pineapples) on indoor tented "greenhouse" shelves -- it has zippered vinyl cover. I originally got it for indoor mushroom growing. -- they did very well in there. I guess those Victorian Wardian and fancy Orchid cases DO serve to provide orchids the kind of environment they need.

If you have a lot of plants, grouping them together creates a microclimate and can increase humidity for the plant in the center of the grouping, so think about who gets the royal treatment. :wink:
Learning never ends because we can share what we've learned. And in sharing our collective experiences, we gain deeper understanding of what we learned.

imafan26
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Location: hawaii, zone 12a 587 ft elev.

Re: Phalaenopsis Help!!!!

Phals come very moist places. Temperature can vary from tropical to nearly frigid. Some places have monsoon followed by a dry season. They are most often found in forested areas and in the low light areas rather than out in the open. When orchids were first brought to England they believe that they had to be kept in steamed hot houses, its a wonder any survived. In actuality many orchids live in places that get rain nearly every day, but the orchids themselves live in the driest part of the rain forest...the trees. Orchid roots are designed to capture water from mist or dew as well as rain but up in the trees they don't sit in water and the roots are exposed to the air so they can dry fairly quickly.

Even some paphiopedilums can be found floating on peat moss in bogs. They are still in the driest part of the bog.

You can tell by looking at the orchid's pseudo bulb, how much water it needs. Paphs and Phals have virtually no psuedobulbs so they come from places that have fairly ample moisture. Besides, it is remarkable how long orchids can last without water. They are very good at preserving moisture.


Catleyas, grammatophyllums have larger psuedobulbs so they don't need to be watered as often and are often found in the crotches of trees but not on the ground. Quite a feat since grammatophyllums can get huge and weigh hundreds of pounds.
Cymbidiums and the oncidium alliance have fine roots and small psuedobulbs so they can store some water. Oncidiums are found in trees and on rocks but not in the ground. Cymbidiums are terrestrial, epiphytic and lithophytic. They are very tolerant of cold weather and actually do better in cooler climates.

Sometimes I find that the best media for me to use is no media at all. I just turn a small pot upside down in a larger one and tie the bare root orchid to the pot or basket. That way I can water every day without killing them. My best growing orchids are growing the outside of the pot and have their roots hanging out. Media actually is there basically to hold the plant in place. Different media and pots lose water at different rates. This can be an advantage or disadvantage, depending on how you water. My orchids are outside, in summer, they need water nearly every day. I would water less in summer if I had them in plastic and bark, but when the rainy season comes they will rot. Bark also breaks down much faster than rocks or no media at all. When bark breaks down it holds on to fungus and mold, impedes drainage and eventually rots the roots. That is why plants in bark need to be repotted before the media breaks down and why I can wait on the rock and no media plants a while longer.

https://www.ranwild.org/Phalaenopsis/mod ... nhead.html
Happy gardening in Hawaii. Gardens are where people grow.

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