When I used to do illustration, I loved water color. I liked the way you could make use of the white paper and how just a bit of color could say so much. especially when painting the sky. So I thought.... what if I try that effect with fabric.... how about fussy cutting around a hand dye and just including a bit of color and lots of white? Applied to a white background, it might look like a faint color wash. and used in a corner, a shading of some sort. and in indigo, it might look like the corner of the sky.
Ragged edge applique over patchwork...of course it really helps if the fabric is very thin, like a fine cotton linen with just a bit of textured slub that has been worn to perfection. I think with a few more little stitches, this will melt right into the background.