Dry cleaning solvent is harsh on wool. Frequent cleaning wears a suit out faster than wearing it does.
The short answer
4–6 wears
When to wash sooner
Wash it now if
- a visible stain
- a smell that survives airing
- the end of the season
What to do between washes
Brush after every wear, hang on a broad shaped hanger for 24 hours, and steam rather than press.
How to wash them
Dry clean the whole suit together so jacket and trousers fade evenly. Cleaning only the trousers is how suits become mismatched.