You're very very welcome! It would be great if you post what you learn about these mites, even what you figure out 2-3 years from now. That's how we all learn!
BTW, here's another pure speculation. Whether or not those mites can overwinter in soil, apparently they live in seed heads. Can they infest collected seeds, either inside the seeds, clinging to them, or hiding amongst them? If they can, try freezing those seeds after you're sure they are really dry. I've red that three days will kill most insects and insect eggs.
(Just be sure that humidity can't condense on the seeds when you take them out of the freezer. Like, double-bag everything in plastic, and/or tightly sealed plastic tubs or glass jars.. I use silica gel from the flower-drying isle as a potent desiccant for seed storage.)
I haven't even learned how to handle weeds in perennial beds. If I can't just hack everything in sight, I can't get most of the weeds out, and they totally take over. More mulch, I guess.
>> I usually harvest seeds from all of my plants so there's no prblm for future patches.
That's great! Do you try to select for certain things? I did that once with blue petunias, very mixed zinnias, and red and multicolor Sweet William Dianthus. I would keep seed separate that came from parents with the traits I liked. But having ALL my petunias fail to germinate one year, and not time or space for zinnias another year, kind of put a crimp in those experiments.
