Upload & Sell: On
A nice series of shots. Technically, I think you did well as it sounds like you are still experimenting with flash. #1 AND #3 are IMO cropped to tightly to the left. In the last, I would clone out the feeder.
Lastly, there is nothing wrong with green or very dark bgs. In the future, think BG. See if you can position your feeder amongst colorful flowers. You might even use two feeders one with a colorful bg and one with a darker BG.
I look forward to seeing more.