Spider mites thrive in hot dry dusty conditions. It is especially a problem on drought stressed plants.
Use the tea on the plants, try to keep them well watered and fed and as healthy as possible. Hose off the foliage to dislodge the mites. Predators usually ultimately control them.
Hose dust off plants in hot weather and make sure plants get enough water. You may have to adjust watering times.
If you commit to a spray program, you will probably also kill off the predatory mites that eat them and you will have to continue to monitor and treat as needed.
Plant other plants that attract beneficial insects and realize that some damage may have to be tolerated.
I have used baking soda spray on spider mites only when infestations are really bad.
1/4 cup baking soda
1 tablespoon insecticidal soap
1/2 cup 70% alcohol
1 gallon of water.
Spray undersides of leaves or dip whole plant in bucket of solution.
1 Tablespoon of horticultural oil can be substituted for the soap, but daytime temperature cannot exceed 85 degrees or there is a risk that the plants will burn. Since spider mite activity peaks in hot weather it makes it difficult to use any oil treatment.