More ideas from Verča
I always do this with the cute fleece blankets at Walmart at Christmas - but I reinforce the sewn part first.

Crochet Collection: How to Crochet Scalloped Edging on fleece blanket (this has the crochet start out by connecting the to blanket stitch on an existing fleece blanket. I'm not sure I trust that blanket stitch on many fleece blankets.