Humidity (Not an issue in my experience)

[mydogmimi]

In my opinion and as far as growing Cattleya alliance orchids is concerned, high humidity is not necessary. I have grown in Southern FL and now in So California. In Florida I was battling fungal diseases constantly...not the case in California. In fact, I would recommend to keep the humidity on the lower side. Of course, cloud forest genera and plants without pseudobulbs this may be a different situation altogether.

[Cym Ladye]

I anyone has ever compared a bloom initiated and opened in 10% humidity with a bloom initiated and opened in 50% or higher, you would see the difference. Most hobbyists not interested in the highest quality of bloom, would not care as long as it bloomed.

[daddydoall]

Orchids are very adaptable if the environment and culture is consistent. Frequent watering and evaporation from the media does raise the local humidity as well. I am successfully growing Cattleya, cymbidium, and Aussie Dendrobium in full sun (RH < 10-20%) on a very hot deck (in LECA / Lava, and coco-chip) with almost daily summer water. however, If you are able to raise the humidity The plants will tolerate much brighter light and much higher temperatures. In my California GH growing a mixed collection, when I put in a swamp cooler and fogger, I was able to close most of the vents, remove the shading and growth really took off (even better than out-doors in full sun).

[rockyfarm]

Higher humidities give one real benefit - orchid fragrance carries and sustains much better! I've added a couple of 'halloween' foggers to my grow room and the air is just more 'alive' now.

[charlesf6]

Oh no..And I already know that I am getting one for a Christmas present...what to do?

The plants have been fine up to now with the only real humidity they have been getting is that in which when I bathe.

[estación seca]

I'd rather look at a big house plant than a humidifier, and they both raise humidity. Pick something that uses a lot of water like a Spathiphyllum / peace lily or Aglaonema / Chinese evergreen. Both of these can stand happily in dishes of water.

Another great water sucker is Brugmansia, the tropical angel's trumpets. They are also great indicator plants for spider mites, too-cold temperatures and insufficient light. Most people can bloom them in an 8" / 20cm pot; they can eventually fill the biggest pot you can move in and out of the house with the seasons.

[charlesf6]

I'd rather look at a big house plant than a humidifier, and they both raise humidity.

Nice idea except for the Evergreen, it might be toxic to the dogs, cats and horses.
Although my ponies don't see much of the house.

[orchidsamore]

I agree with the original statement that orchids do not seem to need high humidity. I am in Florida with high humidity most of the year but we just finished a month with ZERO humidity. Frequent watering supplies all they need.

One caution Thrips exist everywhere in the world and need water as well. In very low humidity they get their water by sucking on flower buds. (Recognizable by buds that look like someone took a blow torch to them). We need to treat with a systemic poison like Orthene and still loss some buds

[Fernando]

Originally Posted by orchidsamore

... but we just finished a month with ZERO humidity.

You don't want us to believe that, do you?

Good humidity and ventilation is crucial for most genera of orchids. As is the tº requirement according to the plant. If you live in a place, where you meet this requirements than you don't have to bother (and you'll tend to consider it less important). When you move, you'll see the difference at once.

[Leafmite]

Two good non-toxic houseplants that raise humidity are banana trees and Theobroma cacao. Both easily take lower light, too, so you can set them behind the orchids.

When my kids were all at home, they were swimmers so we had plenty of showering and damp swimsuits and towels. Humidity was so high that the water would condense on the walls when it was really cold outside. My plants miss that but I certainly don't. :|