I am trying to guess when the best time to spray for persea mites is. The last two years my trees got hammered. Of course, the small things are tough to see....even with a magnifying glass. When to spray???
I hate to push pesticides..but a good systemic works wonders. And unlike sprays,your not having pesticide drift. Fruits are edible after a certain waiting period. I myself haven't tried it on Fruit trees...but that Systemic by Bayer killed off the worst case of thrips and mite and aphids on both a indoor Santol tree and a large Anthurium 'Florida'. Both were easy meals and the systemic worked.
I think also they do make a systemic for Citrus. Saw it at HD.
I agree with systemics. We do use them, but if you have issues with that, then there are other options.
100% Cold pressed neem oil can be sprayed early morning or evenings. It won't kill beneficial insects when dry, but it will destroy over 200 insects. Disturbs their life cycle. Amazon has it. There are a few videos on You Tube about how it works. Takes about 3 days to see results.