Working into the 3rd Loop of HDC
One of my very favorite ways to add a little extra dimension into a crochet design is to use this technique of working into what is commonly called the third loop of half double crochet (hdc) stitches. What it does is it forces the top two loops of the stitch (where we normally work into, either working under both loops or the front loop only or back loop only) to sort of pop forward and sit at more of an angle so that you get this row of Vs sitting on the surface of your fabric kind of like a braid.
Here are a few rows of half double crochets worked into the 3rd loop (seven rows to be exact, if you're wondering!):
The place where you insert your hook is located on the back side of the stitch and it is the loop that is created by the yarn over. It sits just below the top two loops (again, on the "wrong" side of the hdc) at a bit of an angle. Which way it angles depends on if you're crocheting right handed or left handed but it's the first "bar" you'll see down below the back loop of the V on top of the stitch.
You'll find the same sort of bar on the back side of single crochet (sc) and double crochet (dc) stitches, but the loop is much snugger on these stitches and so it's more difficult to work into than that yarn over that's left available with the half double crochet stitch.
If you've ever worked a series of graduated stitches, for example, if you did 5 sc, 5 hdc, and then 5 dc, then you may have noticed that the backside of your fabric will have a slightly different look for those hdc stitches. It's that yarn over that you notice on the back side of your half double crochet stitches!
Let's have a look.
So here's a swatch with those 15 stitches I mentioned above:
And here's the backside of it:
Can you see a bit of those extra looking angled loops in the middle there?
Here, let's point them out with some red:
Those are the yarn overs of the half double crochet stitches, and our target when working into the 3rd loop! They're about the same size
Just for giggles, here are the "third loops" of the single crochet stitches in yellow and the double crochet stitches in blue: