Choosing the Right Mower Blade for Thick Grass and Weeds

Not all mower blades cut the same way. A blade suited to fine, manicured grass may bog down in thick weeds. Choosing the right blade for the vegetation makes the mower cut cleanly rather than tearing and dragging.

Standard blades for general work

Standard, low-lift blades suit everyday grass cutting. They cut with less power draw and suit light work. They struggle in thick, tall growth, where the grass lies over and the blade cannot stand it up. For general mowing, a good sharp standard blade does the job.

High-lift blades for thick growth

High-lift blades have raised tips that create strong upward airflow, standing the grass upright before cutting. They suit tall, thick grass and weeds, because they lift the stems into the blade. They draw more power, so they suit tractors with enough reserve. They also discharge clippings further.

Mulching blades for fine cuttings

Mulching blades have extra cutting edges and a curved shape that recuts clippings into fine pieces. They suit leaving clippings on the ground rather than collecting them. They do not discharge as far, and they draw more power. Choose them where fine mulch is the goal.

Match the blade to the deck

Whatever blade type is chosen, it must be the correct length, centre hole and fit for the deck. A blade that is too long or too loose damages the spindle. Follow the deck manufacturer's approved blade types, and keep the chosen blade sharp. A sharp blade matters more than the type.

Adjust mowing practice for thick growth

In very thick grass, raise the cut height and take off a little at a time rather than forcing the deck through long growth. A sharper blade, the right lift, and a slower pace make thick growth manageable. The right blade turns a struggle into a clean cut.

References

BROWN R T, DAVIES M K. Blade type and cutting performance in dense vegetation[J]. Biosystems Engineering, 2021, 203: 380-388.

Brown, R. T., and M. K. Davies. "Blade Type and Cutting Performance in Dense Vegetation." Biosystems Engineering, vol. 203, 2021, pp. 380-388.

Brown, R. T., & Davies, M. K. (2021). Blade type and cutting performance in dense vegetation. Biosystems Engineering, 203, 380-388.