I struggled with spider mites every season for a few years, until I built up a latent population of ladybugs, initally bought at my local nursery. My balcony garden (between 40 and 100 plants depending on the season) has been big enough to support this, not sure if this will be applicable to yours but I’ll share what worked for me.
The key for me was not using any pesticides and letting the population of mites and aphids swell so there was plenty for the ladybugs to eat - it’s all about getting them to lay eggs, because it’s the ladybug larvae that stick around (can’t fly yet!) and do the most eating, and ladybugs lay eggs where they think there will be enough food for their babies to eat. You want to start a multi-generational war on those mites.
Water the garden heavily at sunset and mist all the foliage so the ladybugs have plenty to drink as well as eat. Make sure it’s dark so they are less likely to fly away. Release them all over the garden, let them eat and lay eggs and begin the war, and keep an eye out for the larvae after a week or so. Don’t use pesticides, and hopefully the cycle continues on and on and keeps all your soft-bodied pests in check indefinitely.
I’ve been lucky to have them overwinter, and I see larvae throughout the year. Haven’t had to bring new ones in since the first couple of releases, but I’d imagine that might have a lot to do with the climate here.
I haven’t tried predatory mites yet but I’m planning to soon, since my new nemesis is thrips, and the ladybugs can’t control those. Tough spot though, since I assume the ladybugs will eat the predatory mites…