Why the usual answer doesn't apply
Most window cleaning advice online assumes a climate with regular rainfall, where rain rinses glass between cleanings and the main enemy is pollen or rain spotting. San Tan Valley doesn't work like that. We get long stretches with no meaningful rain at all, then a monsoon season that makes things actively worse.
So the honest answer is: it depends less on the calendar and more on three specific things.
1. Do sprinklers hit your glass?
This is the single most important question, and it has nothing to do with how dirty your windows look. If irrigation spray reaches a window, that window is accumulating mineral every single watering cycle, and mineral deposits get harder and more expensive to remove the longer they sit, eventually becoming permanent etching.
Windows in sprinkler range should be cleaned on a schedule regardless of appearance. Windows out of range are purely cosmetic and can wait.
2. How exposed are you?
A house backing open desert in San Tan Heights loads up faster than one in the middle of a built-out subdivision. West-facing glass takes more sun and more wind-driven dust than a shaded north side. Exposure varies within a single house, which is why some windows look fine while others look neglected.
3. What are you using the window for?
A view window you look through every day justifies more frequent attention than a guest bedroom window nobody stands at. That's not a cleaning rule, it's just where the value is.
A schedule that actually fits here
- Once a year, after monsoon ends (October or November): if you do only one cleaning, this is the one. You're removing a full season of deposited dust going into the months you'll actually be outside.
- Twice a year: post-monsoon plus spring, the most common choice, and enough for most homes.
- Three or more, worth it if you have heavy sprinkler exposure, back open desert, own a pool with glass nearby, or simply care about the view.
Where the calendar doesn't apply
Two situations override any schedule. Mineral spotting that won't wipe off should be addressed now, not at the next scheduled cleaning. Every month it sits makes it harder to reverse. And solar panels follow their own logic entirely: they're about production, not appearance, and post-monsoon cleaning is the highest-value timing.