Mower blades should be aggressively sharp, but not as sharp as a razor's edge. You should be able to touch the blade with your hand without getting cut. ... Additionally, lawn mower blades that are too sharp get duller, faster resulting in the need to sharpen more frequently and a shorter blade life.

Should lawn mower blades feel sharp?

Mower blades should be sharp, but they do not need to be as sharp as a razor blade. When you touch the blade, you should not cut your hand. That way, they will cut the grass seamlessly and have a clean but. Very sharp blades will get dull quickly and need to be sharpened much more often, shortening the blade life.

Why are mower blades not sharp?

The seemingly dull edge is done on purpose. It's sharp enough to last for 25 hours of mowing (about 25 weeks of mowing an hour each weekend). It's dull enough that it won't get damaged as easily by roots and rocks. Hitting a rock with a hyper-sharp blade will just bend the edge making it less effective.