Thorn Stitch is a simple stitch with lots of possibilities. It's actually a stitch that I knew but kind of forgot about but now I have rediscovered it I'm definitely going to use it more often. I hope you will give it a go to!
There are a few stitches out there that carry the same name. One that is quite different from my 'Simple' Thorn Stitch, is used in Mountmellick embroidery for example. It's more like a Feather Stitch with French knots. The different Thorn Stitches obviously have one thing in common: they resemble thorns. Perfect for my sampler which already has many stitches that look a bit like plants and flowers. :)
Thorn Stitch: how it's done
Thorn Stitch is a couching stitch, which means you attach (a separate) thread to fabric by using stitches. Sometimes couching stitches are meant to be tiny and invisible but it's a different story with Thorn Stitch. The stitches here are practical as well as decorative. For my tutorial I used two different threads: an orange one and a variegated floss. It makes explaining a bit easier. :)
Start by cutting thread from your skein (in my example the orange thread, I will refer to it as the 'central thread/line' from now on). The thread should be long enough to cover the total length of your Thorn stitches plus a little extra so you will be able thread a needle when your done and finish it at the back of your embroidery. Knot the thread (or use another way of starting a new thread if you like) and bring it up to the surface of the fabric. (photo 1) You can now remove the needle and use the same needle for making the couching stitches. Or you can temporarily place the needle safely in the fabric, away from the stitches you are about to make. Make sure the central thread can be moved freely about.
Hold the central thread down with a finger and with your second thread (the lighter coloured thread in my example) make a straight stitch from the upper right to the lower left (photo 2) and again from the upper left to the lower right to form a cross (photo 3). Placing the lower stitches near the central thread will keep your main thread (the orange one) in place.
Because the main thread isn't fixed, it's easy to make the central line curve. Gradually change the position of the central thread for a smooth looking result.
Finish your Thorn stitches by threading your needle again with the main thread and bring the needle to the back of the fabric.
Exploring Thorn Stitch further
Besides using different coloured threads, you can also vary the width of your stitches. Just keep in mind that the lower stitches are preferably close to to the central line. Placing them further away (like I did in the dark green stitches pictured in the photos above and below) will not anchor the main thread securely, you can still move it about a little.
My little exploration in dark green thread may not have been a very effective couching experiment but it did proof to be useful in another way...
If you are not happy about using a separate thread for your Thorn Stitch, consider making one very long loose stitch (your central thread) and add Thorn Stitches with the same thread to attach the central thread to the base fabric. I tried it out (see below) and I think it works especially if you are looking to make a simple curved line and don't need or want the 'freedom of movement' that the traditional Thorn Stitch method offers. Be careful not pull the thread through when you make that first loop though, or you'll end up with a very long, straight stitch! Hold the loop down with your finger as you place the couching stitches.