There is no definitive answer to this question as it depends on a variety of factors, such as the type of soil you have, how often you use your tiller, and the condition of your tiller blades. However, most experts recommend replacing tiller blades every two years or so.
If you have clay soil, for example, it’s important to replace your tiller blades more often than if you have sandy soil because clay soils are harder on equipment. If you use your tiller frequently – for example, if you’re a gardener – then it’s also important to replace the blades more often than if you only use it once or twice a year. And finally, if there are visible nicks or cracks in your blade edges, then it’s definitely time for a replacement.