Deep-clean before the rush

What is changing this month

Autumn traffic is building and birds are crowding feeders again, which is exactly when pathogens spread most easily.

Birds to expect in September

Dark-eyed Junco Winter visitor White-throated Sparrow Winter visitor Rose-breasted Grosbeak Seasonal Ruby-throated Hummingbird Seasonal Pine Siskin Irregular American Goldfinch Year-round Blue Jay Year-round

Most often reported at feeders this month. What turns up depends on your region and the weather, so treat it as a starting point.

Feeder jobs for September

• Do a full strip-down wash of every feeder.
• Disinfect with one part bleach to nine parts water.
• Keep nectar out until you have seen no hummingbirds for about two weeks.

Water in September

Clean the bath before autumn traffic builds. Summer algae and debris should not carry over into the busiest season.

What to watch for

• This is the month for a full strip-down wash before autumn crowds arrive.
• Soak cleaned parts for ten minutes in one part bleach to nine parts water, rinse and dry fully.
• Keep hummingbird feeders going until you have seen no birds for about two weeks.
• Ground-feeding sparrows arrive now — scatter millet, and rake up waste.

Three things not to do

• Don't skip the deep clean — autumn crowding is when disease spreads.
• Don't take a hummingbird feeder down early; leave it until you have seen none for about two weeks.
• Don't put feeders back together wet.

Check this locally

Timing shifts with latitude, elevation and the year. Use these as pointers, then check what is actually happening near you.

• North: first hard frosts can arrive; watch for early winter visitors.
• Mid-latitudes: peak autumn movement and the busiest feeder month.
• South: summer birds may still be present alongside arriving winter ones.

Questions this month raises