A big migrating group came through your area in March to head north so you might consider putting the feeder up earlier next year. What you may have been seeing in August was the big migration back south again for winter. You could also try planting some plants that they like (salvias, honeysuckle, etc.) and you might be able to attract some summer residents!

bbalm,
There have been hummers in the Atlanta area for quite a while. I am in NY and I have at least one feeder up by the middle of April.

Penny

Okay! Maybe this year, since they've found me, I won't be out there by myself! (These are the ruby-throated.) Thank you. I actually do have the feeder in the middle of a huge hummingbird garden, so I think they will like me! Although, this week the recyclers chopped my trumpet vine down to its bottom while struggling to pull out my bin, so now it has to start all over! :(

I live north of Atlanta and have had hummers for about 3 weeks now.