Darning also refers to any of several needlework techniques that are worked using darning stitches: 1  Pattern darning is a type of embroidery that uses parallel rows of straight stitches of different lengths to create a geometric design.f enough threads are criss-crossed over the hole, the hole will eventually be covered with a mass of thread. Fine darning, sometimes known as Belgian darning, attempts to make the repair as invisible and neat as possible. Often the hole is cut into a square or darn blends into the fabric.