It is a good idea to keep your digging tools sharp because you’ll get more work done in less time and with less effort. Sharpening is easy. All you need is a pair of leather gloves, a 12-inch mill bastard file, and a vise.
Secure the tool in the vise by its handle—dish-side up, in the case of shovels and posthole diggers, and blade pointing straight up for hoes.
Hold the file against the original bevel on the cutting edge. If there’s no bevel, tilt the file 45 degrees off the tool’s face. Push the file straight toward the handle in even strokes. Sharpen only on the push motion of the file; not the return pull.
Check for a small burr on the sharpened edge. Remove the burr, which forms as you file the metal. A couple of strokes is all you need.