Last winter, Lilo ate a 2-inch-diameter half-moon out of the front placket of my favorite winter cardigan. It’s semi-felted wool and I’m not a knitter, so I wasn’t sure how to fix it and left it hanging on a hook where I would occasionally stare at it while trying to come up with a fix.
The solution turned out to be so simple, I felt silly for taking so long to think of it.
I cut a section out of the generous placket backing. The part I cut out was twice the size of the half-moon so I could fold it over to match the folded edge of the placket, plus a little extra. I used my sewing machine to zigzag stitch around where I had removed the material.
I trimmed the edge of the scrap to match the front side of the hole and used matching thread to sew it in place. The fabric is pretty thick, so to hide the stitches I pulled them diagonally through the fabric and left only one millimeter or so visible at the top (highlighted in red).
This is how the front looked when I was done stitching:
I did the same on the backside.
After:
While I was at it, I decided to fix something that has always bothered me about the sweater, which is the way the plackets overlap crookedly at the hem:

I trimmed the hem to even it out and finished it off with the zigzag stitch:
Much better!
So crafty, looks great!
Why thank you! You will probably have the opportunity to see it in person soon!