Azamax or Azatroll. Both are neem oil concentrates. They mix easy with water and can be sprayed or added to the rez as an anti-feedant. Mix some up and put in rez and watch the hella two-spotted spidermites drop off dead. Clones and seedlings can be dunked in a solution.

The anti-feedant way is the only way for me to keep them away. At least that way even if they are near they don't want my stuff. LOL