One of the really nifty aspects of Elizabethan polychrome embroidery, is that it was the foundation for stump work. Butterflies had free floating wings, pea pods opened to reveal pearl "peas," flower petals could wave in the metaphorical breeze. Of course, the extant piece that I want to reference evades me, at the moment, but you can get an idea of what I mean by looking at this sweetbag, from the Met: http://www.metmuseum.org/art/collection/search/81553?rpp=30&pg=1&rndkey=20140924&ao=on&ft=*&deptids=8&when=A.D.+1400-1600&pos=1
First step was to outline the peas in split stitch with the main green thread. (Pardon my photo lighting, please. I need a new camera desperately, but that will be an expense for much further in the future.) After the outline stitches were done, I did a fill of the bottom layer of the pea with a darker green thread, in detached buttonhole. (Sometimes, detached buttonhole just does not want to stitch evenly, but this time, luck was on my side. I try to keep an even tension, and do not pull the stitches tight, because the next row is stitched into the last row and if the stitches are tight, you will be fighting to get the needle through.)
After the bottom layer was done, it was time to start the top layer of the pea pod. Again, this is done in detached buttonhole. Now, if you crochet or knit, you may understand the mechanics better. The last stitch in the row does not get tacked into the fabric. You turn the needle and start a new row, returning back the way you came. I added two stitches into the first stitch after turning, so that the top layer of the lea pod would extend out, like the bottom (where it comes to the point, if that makes sense?) You can kind of see in the picture to the left (this is the second row I am working on.)
I just kept stitching back and forth, until the top layer of the pea pod was about the size of the bottom. Now, end where the pea pod joins toward the stalk, I did attach to the fabric, so that the pea pod did not fully open. After a few rows of this, I carefully whip stitched my remaining thread down the side of the top layer and then tied off under the fabric. Here are some progress pics.