The Seed Stitch,
like its counterpart in embroidery, is merely
two small Satin Stitches right next to each other. It makes
a little dot on the pleated fabric, covering 2 pleats.
Hints:
Be careful to keep the tension
even on the two stitches. The stitches should be just
tight enough to draw the pleats together slightly,
but not pinch them.