I had mites for about 1 year.... tried about everything to get rid of them....you can kill the adults its the eggs that hatch every 3-4 days that get us.

The only thing I have used that totally inilated the spider mite
(attacked their nervous system and made them sterile:thumbsup

was a product called AVID

Avid pesticide features a unique chemistry which provides a different mode of action to control mites and certain insects. The active ingredient is derived from a soil microorganism and is chemically unrelated to any other miticide or insecticide. When applied to target insects, it kills both by contact and ingestion. Avid acts against all mobile forms of mites & kills leafminer larvae as they begin to feed and also stop egg-laying in adults
Apply to seedlings or clones after they have rooted.....residual effect of 2 months

Product can not be shipped to California