Short answer
Spring — once freezing nights are over — is the best time in the Treasure Valley, because it clears a whole winter of grime and grit. Early fall is a close second. If you plan to seal the concrete, wash first and let it dry fully before sealing.
Why spring
Winter leaves driveways covered in road grime, de-icer residue, tire marks, and dirt tracked in from wet weather. Washing in spring resets the slab for summer, when you're outside the most.
Other good times
Early fall, after irrigation season and before the freezes
Before listing a home or hosting a big event
Before sealing — concrete needs to be clean and fully dry first
What we avoid
We don't pressure wash when temperatures are near freezing, since water left on the slab can freeze into a slick hazard. Oil and rust get pre-treated before cleaning — see rust stains on concrete.
Rather have a pro handle it?
Pro Solutions does pressure washing across Boise and the Treasure Valley. Quotes are free, itemized, and usually texted the same day.