Not only does a sharp blade keep your mower in tip top shape, but it can actually improve the look of your lawn. Dull blades can tug and rip grass instead of trimming it gently. Lawn that looks ragged may mean it's time to take the mower blade to the hardware store for a professional sharpening. If you choose to DIY instead, you'll need a grinder and some thick work gloves.
Related: 7 Tips to Keep Your Lawn Mower in Perfect Working Order