Seeding mat to increase humidity

[Spangler]

Good day all
I have been lurking the forums as a guest for a while and finally got registered. I have been seraching several sites and forums and my question is if you place a seeding mat under a humidity tray will that help increase relative humidity? Or is a warm mist humidifier the better option. Im a window sill grower with plants on south side. I have no way to isolate the plants in a seperate room. Thank you in advance for any suggestions and please forgive if this was addressed else where I tried the search and nothing specific came up.
Joe

[ezil]

Welcome, and thanks for asking that question. I'm afraid I have to start with the typical orchid grower's phrase: "that depends...", namely on your growing conditions, your set up and the orchids you grow. There are advantages to both methods. If you are trying to raise the humidity around the leaves of the plants with a heat mat, it will only work with small(er) plants: a big oncidium would not benefit from this approach. You'd also have to enclose the growing area, so that the little humidity this provides, does not evaporate. The advantage would be if you had warmth loving plants growing in a cooler area. The mat would provide extra warmth at root level. You may have to fill the tray up more often and change the water. A humidifier would work if the plants are taller, but there again: you'd have to enclose the area, or all is for naught. I hope this answer isn't too ambiguous. Others, I'm sure, will chime in as well.

[Junebug]

Joe,

I can't help you with your questing but it's really helpful if we know your growing zone. If you list it on your statistics page it will pop up every time you make a post.

[Zoi2]

Hello and welcome.
Joann

[Wjs2nd]

I use a warm mist humidifier, a cheap vicks one.

[RosieC]

Welcome to Orchid Board.

There is an argument (which I agree with) that says that humidity trays won't help because unless they have sides up above the plant (so like a tank). This is because the water vapour generated just above the water will just flow down off the sides (being heavier than air) and will never reach the plant but just drop to the floor.

That being the case while the seedling mat might increase the rate of evaporation of the water in the tray I would have expected it to still just flow to the ground.

To get a humidity tray to do anything you need sides which come above the plant, so that it can't flow out until it has already gone above the plant. A mister throws the vapour up into the air, and while it will still drop, they can maintain a level if the air in a small area, or produce enough to humidify the whole room enough to make a difference. The amount of water in a humidity tray is not enough to humidify the whole room.

What sort of orchids do you have, Phals, Dens, Paphs, Oncs might not need any extra, although that could depend on you natural humidity, I don't use any extra where I live, but if you are in a dry place like Arizona the same might not be true.

Other types of orchids that need high humidity (like Plurothalids) then you might need to think about a tank of some sort. Take a look at our Terrarium growing section for ideas on that.

[Ray]

From a scientific standpoint, adding heat will result in a faster evaporation rate. Whether that results in an appreciable increase in the local humidity is the questionable part, as others have described, especially when you consider that the heating mat will only increase the temperature by about 10°F above ambient.

A warm-mist humidifier, by contrast, literally boils the water at its heating element, resulting in a much great evolution of water vapor.

[Spangler]

Thank you for the information I will keep all thought in mind. Humidity tray may not work but i am in the cant hurt side of the fence since my options are limited.
Joe

[camille1585]

In any case putting a heat mat under your orchids is a good thing if you don't live in a warm climate; the extra heat at the root zone will stimulate faster growth.