I don't often appreciate how fortunate I am to not worry about irrigation zones -- I remember visiting with my sister in eastern Washington and she was drooling over some sort of water system doo-dah at the pipe store as I tugged at her to go look at the plant rack outside...
That said, I did lose some plants last fall when we had that dry spell in Aug-Sept and I never even thought to water until some newer plants just withered up and died. Oopsie.