Lady bugs

So I waived the white flag. Sprays aren't takin care of the spider mites. I'm 4+ weeks into flowering. So I just ordered 1500 lady bugs from amazon. Anyone order from there before? I'm worried with the cold temps outside if they will arrive alive.
If and when they do show up alive, is there anything I can do to make their stay more comfortable? Where do they get their water from, the soil?

Also, I only have 3 plants. About 4 feet tall. Should I unleash all 1500 on them? Seems excessive. Any recommendations on how many per plant?