
I've been wanting to try this technique (I'm going to call it a "shadow" technique, because I don't how else to describe it) on a canvas for some time. And now that I have a small canvas to experiment on, I'm eager to give it a try.
You need to have a fairly big area to fill - and the pansy petals should work just fine - and then you pick out a smallish pattern that fits the area you're stitching. I chose a oval repeat pattern, sort of a diaper pattern really, to echo the organic petal shapes. I think using an upright, straight stitch works best, because you WANT the canvas to show thru. If you use a diagonal stitch, the thread will cover the canvas more completely and not much of the canvas will show. And in this case, you want the colors on the canvas to show thru.

I'm using just one strand of DMC Floche (my current favorite thread) for all the stitching thus far (you can also use 1-2 ply of floss or silk).... You can see that even though I'm using just one yellow color, it LOOKS like I've shaded the colors on the canvas. I'll continue stitching over the black stripes too. (I plan to tent stitch the white and orange center areas, then put straight stitches - or narrow bullions - on top for the stripes. That's my plan, anyway.)
And I've done the same treatment on the blue petal. It's harder to see because of the darker color, but I'm using a royal blue thread (in a slightly smaller version of the stitch pattern) to cover the whole blue petal, yet the shaded canvas is showing thru, so it seems like you've changed thread colors.
In the background, I've started stitching rows of basketweave stitches, but leaving two canvas rows blank in-between. I'm hoping it will look lacy but fuzzy, if you know what I mean. And I think I'll do any distinct leaf areas in a full basketweave, to stand out from the sketchier background stitching...
As for the borders, I might do the same padded borders as I did on the Gerber Daisy, but I'm not sure what I'll put in the middle row. Checkers? Stripes? or just a shaded band? I'll just have to see what looks best when I get to it!






