I just moved Detroit Mi. last year and am wondering when I can start planting some flowers here. I am from Atlanta and there everything is in full bloom.

Hey, Corvetteking! Welcome to a whole new gardening world! Why you'd leave Atlanta to garden up here.....well, never mind, lol!
Here's the website for the Michigan University Master Gardener Program.
http://web1.msue.msu.edu/mastergardener/
When you get to the site, at the top go to MG COUNTIES and click on LIST OF COUNTIES; a Michigan County map will appear; then just click on your county to locate the MG office nearest you (there is one in Detroit). You will be awed at how many questions they know the answers to!
Have fun with your new gardening zone!