Can anyone help with my dahlias? After the first bloom, they have just dropped their stems and are looking sick.
You'll wanna deadhead those old blooms and that plant should be looking fine and dandy after that.
Hmmm...how often are you watering? Is it possible you're watering too much?
You can remove the deadheads, as Ed said, and also remove the old yellowed leaves and it will be fine once again.