WTF is it with people and wanting to use pesticides on plants when there is no need for it.
A simple quick and easy solution to spider mites costs as little as a cup of coffee.
Get hold of a bunch of chilli's and soak them in distilled water over night (cut the ends off them to allow water to seep inside).
Get a spray bottle and pour the soaked chilli water in a spray bottle and put a little bit of dish washing detergent in the water and add plenty of crushed garlic.
Give the spray bottle a nice little shake and you have yourself a cheap natural alternative that spidermites DISLIKE with a passion
Garlic and Chilli's are natural best deterents. If your growing outdoors then try grow some Garlic around them. this will help keep pests away. Alternatively keep some freshly cut hanging around the tree. The odour is something most pests can't stand.
When was the last time you ever saw worm holes or spider mites eating a Chilli or a Garlic
There are some natural products available with these components already pre-made of which also work great. The benefit of this mixture is that it can be sprayed on stems, buds, leaves(both sides) and won't harm the plant in any way shape or form.
Give it a shot