Media for indoor low humidity?
 

I'd love to hear some discussion about how to best grow the unifoliate species indoors (low humidity ~30%, usda zone 6), particularly in terms of potting media.

Ive had an okay experience with sphagnum in terra cotta pots with packing peanuts on the bottom, but I'm learning towards trying plastic pots instead. I'm guessing I should definitely stay away from the leca-in-a-mesh-pot approach that folks in Florida use!

My growing conditions are quite different, a lot of outdoor growing - where the humidity can be quite low. I don't think Catts are all that sensitive to humidity - they have those big, fat pseudobulbs to give them reserves. But in general, my approach to an environment with low humidity is to simply water more often. Depending on temperature, that could mean every 2-3 days for Catts, as much as daily for orchids that don't have the reserve capacity of pseudobulbs. (Like Pleurothallids and Vandas) With low humidity and a well-drained medium, you don't have to worry about overwatering.

If you've learned how to water sphagnum, changing from clay to plastic will probably be beneficial in your conditions. Try with just one, repot at the proper time only, and get the sphagnum less damp at first as you learn how long it takes to dry.

I grow mostly bifoliate Catt species and a few unifoliates in extremely low humidity conditions. Generally %s in the teens or even single digets. Also temps frequently break 110f in the growing space.

Because these are the conditions i have, i stick to Cattleya and I grow SemiHydroponic. I find that S/H allows plants to keep cool and provide constant moisture at the roots which seems to make up for the extreemes in heat and dry.