I made two of these hanging planters, one out of old leather and the other denim. I will show you how I made the leather one but the principle is virtually the same for the denim one. You can see the instructions for that on the blog (link at end of post).
You can use any old leather, I got mine from a discarded sofa but an old jacket or handbag would do. Faux leather will work just as well as real leather.