Humidity and temperature fluctuation

[PHRAG]

What effect does fluctuating humidity have on orchids?

Specifically, from a range of 60% fluctuating up to 90% and higher humidity over the course of a few hours, and back down again. I am trying to understand if this type of fluctuation can be harmful, or if orchids don't really mind. How sensitive do you think they are to this type of variance?

What effect does temperature fluctuation have on orchids?

Within normal temperature ranges, let's say between 80 degrees F and 70 degrees F but fluctuating a few degrees up or down each hour?


The reason I ask is this: I am trying to set a standard in my growing area so my plants get into a routine. What I am finding is that I can control temperature and humidity fluctuation to a certain extent. And some variation occurs on it's own as well. But as long as I am within optimal growing ranges, is fluctuation going to do anything positive or negative?

 

[Rick]

Temperature and humidity fluctuations are part of natural systems where orchids are found. The magnitude of these fluctuations vary from one place to another and season to season.

A daily temp variation of about 20 F day/night is normal. Over a five minute interval 5 F is no big deal. When I take orchids to show and tell night at the orchid society meetings they go through much bigger shifts than this, and generally don't have a problem, but a change of this magnitude only happens a couple times a year per plant (not multiple times per day).

Pretty much the same for humidity.

In general the more stable the better for long term growing.

 

[Marco]

How about recently out of flask compots and the like. Will temperature fluctuations like this be bad?

 

[PHRAG]

I am starting to see this sort of pattern in the fluctuations in my growing area. The humidifier is set to come on four times a day for an hour. The humidity spikes to 85-90% during this time, and falls to around 60-65% in between. At night humidity can go as low as 50%.

During the time that the humidifier is on, the temps raise 2 degrees in the greenhouse. At night I see about a 10 degree difference.

I am more concerned about the spikes in humidity than temperature, because the humidity seems more drastic. But whether it is harmful is my question. I know consistency is good, but is there a time where fluctuation can be good, in this case with humidity levels going up and down but always within a positive range?

 

[Rick]

What effect does fluctuating humidity have on orchids?

Specifically, from a range of 60% fluctuating up to 90% and higher humidity over the course of a few hours, and back down again. I am trying to understand if this type of fluctuation can be harmful, or if orchids don't really mind. How sensitive do you think they are to this type of variance?

It also depends on the species. I can't imagine any Catt having a problem with this type of fluctuation on a day in day out basis, but I've had Draculas drop buds after one day of this type of bounce, and have pretty big problems loosing leaves if this goes on for weeks.

 

[PHRAG]

I am talking about phrag besseae, paph rothschildianum, phal species like equestris and violacea, and my Neofinetias.

 

[PHRAG]

Ok, I think this humidifier has got to go. I just went in there and the humidity was 95% and everything has condensation on it. That can't be good. I just don't know what to do about the spiking. With no humidifier in there I get 50% humidity and that isn't quite enough. But with a cool mist or warm mist humidifier in such a small space, I get massive amounts of humidity. Damn, and I just about thought I had it all figured out.

 

[Rick]

I am starting to see this sort of pattern in the fluctuations in my growing area. The humidifier is set to come on four times a day for an hour. The humidity spikes to 85-90% during this time, and falls to around 60-65% in between. At night humidity can go as low as 50%.

Instead of using a timer I would use a humidistat and lock it in to about 70-80%

In general I think 50% is too low for most of the stuff you are listing, especially if your phals are mounted.

Your temp fluctuation is not a problem

 

[PHRAG]

How would I go about hooking up a humidistat to a cheap humidifier? Do they make a plug in version that kicks the humidifier off and on?

 

[Rick]

Humidistats are just like thermostats. They are just switches, but actuated by temp or humidity rises and falls.

WW Grainger has humidistats in their catalog, and you should be able to wire the main hot lead of your humidifier right through it.
I'm pretty sure I've seen humidistats listed in some of the big GH supply catalogs too.

Presently I'm using a scavenged humidistat out of a cheap drugstore room humidifier. I cant remember what brand it came out of, but it has a humidistat in it to turn a fan on and off that blows past the wet wick. After busting the case apart, I just cut the wires off to the fan and wired it to the solenoid valve of my misters.

 

[Heather]

You might be able to find a humidifier with a humidistat built in. I can set mine to say, 75% and it will come on if it dips below that. The only issue I have using mine on this 'auto' setting is that the wicking filter dries out and then I have problems getting the thing to work.

 

[Rick]

You might be able to find a humidifier with a humidistat built in. I can set mine to say, 75% and it will come on if it dips below that. The only issue I have using mine on this 'auto' setting is that the wicking filter dries out and then I have problems getting the thing to work.

The next step to that is adding an auto-fill system with a float valve or fill switch to keep the tank full.:wink:

 

[paphioland]

roths like high humidity 80-90%. And as most know like a temp drop into the 40s-50s in the fall at night