Another solution, which will often be better if your images are vector and a little stretching is okay:
border-image-repeat: round;
This also far more easily lets you have different butt images. See https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/P... for info and examples.[dead]
The image chosen to demonstrate this idea depicts twining vines; it isn't just a series of "independent" abstract blobs and ignoring that fact leads to some awkward / inelegant shapes.