The short answer: twice a year - autumn after leaf drop and spring before the storm and Fire Danger Season. The longer answer depends on your suburb and what's overhanging your roof.
Why twice a year?
Adelaide's autumn (April-May) drops massive amounts of deciduous leaf litter in inner-east suburbs like Norwood, Burnside and Unley. Spring (October-November) brings storm season and the start of the SA Fire Danger Season on 1 November.
Suburbs that need more
- Hills (Stirling, Aldgate, Bridgewater, Crafers) - year-round gum fall plus bushfire prep. Quarterly is the practical rhythm.
- Heavy-tree inner-east (Burnside, Norwood, Unley) - autumn loads are heavy. Quarterly during peak season.
- Coastal (Glenelg, Henley Beach, Semaphore) - less leaf load but more salt and grit. Twice yearly plus after major storms.
The CFS deadline
For any property in a BAL-rated bushfire zone, the CFS recommends gutters cleaned before 1 November (start of Fire Danger Season). Many insurers now require it as a policy condition.