Chryss, I was not trying to imply the Merit has any miticidal action. Rather, if one gets into a situation in which you have insects and mites, and happen to think the insects need immediate attention, don't be anxious to use the Merit, or you'll be sorry later.
Chryss - You may need to spray 3 times in a row, since you will be missing eggs and fertile females that got away the first 2 times. Five to seven days between applications depending on the temperature. The best miticide I've used is Avid.