A good strong spray with plain water, every day for 3-7 days, then once a week to maintain control. Sometimes a little hard on plants that like to dry out between soakings.

I agree, you need to change the environmental factors that they like.

Of all the cures - predators, acaricides, neem oil, soft soap, spraying - you can't beat putting the plants in the rain for a day or two!

If the plant has a degree or two of hardiness then exposure to cold.
Or as previously said high humidity if the plant will tolerate it.
I've also used an emulsion of garlic water and olive oil but as with all emulsions it is best to test it on a small area first.