Difference Between Mulching Blade & Standard Blade

Cutting Edge

• Mulching blades cut the grass blade similarly to a standard rotary mower but have a cutting edge that extends all along the blade. Rotary mower blades, in contrast, have cutting edges just at the blade's tips. The mulching blade's extensive cutting edge re-cuts the airborne grass clippings as they swirl under the mower's deck.

Curve Angle

• Standard rotary blades curve upward, scooping the lawn cuttings into a horizontal swirl that blows the cuttings toward a side or rear discharge. The curve is just opposite the cutting edge and, like the edge, only appears at the blade's end. Mulching mower blades are much flatter, having only a slight upward curve opposite the cutting edge. This design blows the cuttings vertically, where they encounter the blade multiple times before falling.

Cross-section

• Not only do mulching blades have a longer cutting edge, but, when looked at from the side, the blade angles up toward the deck before returning to its original height, looking somewhat like the cross-section of an upside-down saucer. This gives the blade a greater chance to contact the whirling grass debris. The shape, combined with the blade's curve angle, ensures the blade dices the lawn clippings into quickly decomposing pieces.

Other Differences

• Transforming your standard mower into a mulching mower isn't as easy as simply changing the blade. The deck, or body, of a mulching mower is usually taller than a standard mower's deck, in order to give the angled mulching blade room to effectively shred the clippings. Mulching mowers often have more horsepower than standard mowers, due to their higher workload. If you do use a conversion kit, be aware of its limitations.