I used a can of insecticide years ago that worked like a fog and had wonderful success with killing pests. It also helped clean the greenhouse of them. After I did add some garden spiders to the room to set up housekeeping for when the aphids came to visit.

It isn't so much the internal plant moisture that deters the Spidermite, rather the external humidity. Years when it is very dry I used to set the sprinkler on them for 30 minutes or so each evening and that moisture lasted all night and didn't cause 'moisture' problems but did seem to deter Spidermites.

Great advice Ruth Ann! Nice to hear from both of you again!

Great to hear from both of you.
Will, did you retire?
Jerry

What systemic are you using for spider mites? This is the worst year I've ever had for spider mites and the first where I've had spider mite problems outside more than the remanents of ones from inside when the plants go out in the spring. I've hit the brugs with Forbid spray twice and an "organic" spray once. And now the mites are back again. I've got buds too so a really strong hose spraying is out.

Of course, this has been a most unusual year in the Washington DC area: the warm, cold, warm winter, scads of triple digit days, drought, then unusually cool summer days, days of rain, the derecho, the earthquake a year ago. It hasn't been global warming here this summer; its been global climate craziness. Of course one summer doesn't a climate make; but what's going to happen here next?