posted 17 hours ago
My mom bought one of those in the 70's.....they work well, ask me how I know. Had a name, 'Hula Hoe', pretty sure.
No need for super sharp, they work below soft surface and really are for just disrupting/tearing the weeds (or unwanted/needed nature's medicine) as they get established.
If you think about it, sharpening with a file beveling from the top down would make the blade a bit self sharpening as the bottom of the hoe wears away. In hard ground, sharpening from the bottom up would keep the keen edge away just a bit. Doubt it matters.
For hard ground, we weld hard facing on the top of backhoe tooth or bucket edge, bottom wears away faster tooth stays sharp.