Welcome to the PNW and to ATP. I am on the wet side, so everything is much different for me. I do know that my sister (Lauribob here on ATP) lives on the dry side and she has to pay close attention to zones when purchasing plants. You might want to check out the PNW forum as well to get a feel for what folks are planting and when. I hope you settle in well to Spokane, I sure love the river running through town!