I have a good condition Oak floor that I just sanded down using a flat vibrating sander for the whole floor except for aa spinning edge sander for the edges. The middle of the floor looks AMAZING after applying the stain, but the edges are SOOO much darker. I've applied a thick coat of dark brown stain but have not put down the polyurethane.

What is the best way to fix this?

Any help would be VERY appreciated!

You will need to resand the floor. The sanding progression we use to get stan to take evenly is; drum sand with 50 grit, edge with 50, edge again with 80 grit, drum with 80, then palm sand edges with 60 grit. Then hardplate with a 100 grit sand paper, then buff again with 100 screen. We also water pop prior to staining.

Jitter bug the edges, if you are using a square oscillating sander.

You can blend by hand sanding, too.

Unfortunately, you have to start over.