You could try working an increase in the bo row.
One I've used for a stretch edge is:
*bind off 2, YO, bind off the YO; repeat from *
That didn't create a flare, it just made it more flexible. I think if you worked an increase like a M1F or M1B, that could create more flare. If not, you could try doing it between every stitch, rather than between every pair of stitches.
Hope that helps...