Humidity (Not an issue in my experience)

[estación seca]

It depends on the plants. A lot of Cattleya, Phalaenopsis and Vanda alliance hybrids don't mind lower humidity. Some orchid groups do mind very, very much.

[rbarata]

Originally Posted by estación seca

It depends on the plants. A lot of Cattleya, Phalaenopsis and Vanda alliance hybrids don't mind lower humidity. Some orchid groups do mind very, very much.

True, I'd love to grow draculas but I know they couln't make it.

[Leafmite]

I agree that it really depends upon what you are growing. Many of the cloud forest orchid species (i.e. Lepanthes, Lepanthopsis, Platystele) do seem to need that higher humidity. I need to grow them in a tabletop greenhouse, along with a few of my smaller Bulbophyllum, even though I don't have as low humidity as you do.