When to treat tree to prevent rust mites?

I had some pretty bad rust mite damage on my oranges last season (I posted about it here: What’s wrong with my orange tree? back in Nov). I got advice from several places that I should treat the tree with neem oil this year to prevent mites. What I don’t know is when I should treat the tree.

I am in Tampa, FL. The tree currently has flowers in bloom.

Thanks!