Dwarf Asters

I had never heard about these flowers, but when we saw them at Home Depot, they were standing up and liking the cooler weather.  We read the stick in them and it says they bloom from early Spring until Late Fall.  They look like keepers to me.

Mystery Plants-Any idea what it is?

You probably can't see this plant good enough to identify it for me. I "thought" it was a Blue Aster plant, but it has grown so large, at least 3 feet tall, I'm wondering if I've been lovingly cultavating a WEED all Summer long. If it is an Aster, this corner of my little garden is going to be spectular when it blooms next month. I have my beloved Shasta Daisy in front of it. This plant overshadows my huge mums that are behind it.