Spider mites on pleurothallids and other minis; treatments?

[mremensnyder]

Okay, so recently I have acquired some micro miniature pleurothllids that I am growing in glass orb terraria near a window in my apartment.

Through this past fall, winter and spring I kept some houseplants in the apartment, all of which acquired severe spider mite infections while indoors. All of the survivors are now on my screened porch but the spider mite issue seems even worse on the porch than inside. I have recently treated some of the plants with systemic insecticide and will be treating the rest of these houseplants now on the porch shortly.

Initially, I assumed that my mini orchids in the little terrariums would be safe against the spider mites because the environment inside would be very humid and wetter than spider mites might like. Thinking about it further though, clearly spider mites are present in high numbers in both my indoor and outdoor environment and I am afraid it is only a matter of time before my orchids develop spider mite infestations. I am not sure the high humidity alone will ward off the spider mites. Additionally, orchids this tiny (for example Lepanthes telipogoniflora) would seemingly succumb to these mites within days if not hours once the infestations begins.

So I guess I will have to keep a very close eye out for signs of infection, as it seems inevitable here. If and when I do notice it, what can I safely use to treat micro mini orchids that will not flat out kill the plants? Perhaps I could soak each plant in water for an hour or two each week to drown any mites starting to take over?