Germinator,
Based on the date when I got hit with the Mites in 2010, I commenced spraying in 2011 two weeks earlier. While it may have been "luck" in 2011 that we didn't have an infestation - I figured preventative spraying would be the best insurance.
Gary,
That is a very good suggestion - and Organicide is probably more widely available throughout the country.
Raybo