The presence of dew on your lawn indicates that you should delay mowing. Mowing grass that is still wet from morning moisture is highly discouraged by turf management experts. Saturated grass blades and soft soil create problems for the health of your lawn, the longevity of your equipment, and the safety of the operator. Waiting for the turf to dry will prevent issues that arise from cutting a wet lawn.
Why Wet Grass Damages Your Lawn
Cutting wet grass subjects the plant to a tearing action rather than a clean slice, severely stressing the turf. Water-laden grass blades become heavier and bend under the mower deck, resulting in a ragged cut that leaves the ends frayed and vulnerable. This poor cut quality leaves the grass with a greater surface area for moisture loss and creates an entry point for various pathogens.
When the mower cuts wet grass, the heavy, moist clippings stick together and exit the discharge chute in thick clumps. These dense piles settle on the lawn surface, blocking sunlight and air circulation from reaching the grass underneath. The resulting smothering effect quickly leads to patches of dead turf, compromising the lawn’s uniform appearance.
The damp, injured grass provides an ideal environment for the spread of fungal diseases. Water acts as a transport medium for spores of common lawn ailments like brown patch or dollar spot. The contaminated mower blades efficiently distribute the infection across the entire lawn with every pass, turning a localized issue into a widespread problem.
Risks to Equipment and Operator Safety
Mowing wet grass significantly increases mechanical strain on your equipment and accelerates wear. Sticky wet clippings quickly accumulate inside the mower deck, reducing the airflow necessary to lift the grass for a clean cut. This buildup forces the engine to work harder, leading to reduced efficiency and potential overheating or component failure.
The constant friction of moist grass against the blades causes them to dull much faster than when cutting dry turf. Dull blades perpetuate the tearing action and further strain the engine, creating a detrimental cycle. Leaving wet grass residue on the mower’s undercarriage promotes rust and corrosion, shortening the machine’s service life.
Operator safety is a serious concern when working on a wet lawn. The saturated grass provides a slippery surface, increasing the risk of slipping, especially when mowing on slopes or making turns. A sudden slip can cause the operator to lose control of a walk-behind mower or be thrown from a riding mower, leading to injury. Using electric or corded mowers in wet conditions presents the hazard of electrical shock.
Ideal Timing and Mitigation Strategies
The most effective strategy is to wait until the grass is completely dry before mowing. The ideal time to cut is mid-morning, typically between 8 a.m. and 10 a.m., after the morning dew has evaporated. This window allows the turf to dry out but avoids the high heat and stress of the midday sun, which can cause the freshly cut ends to suffer from dehydration.
If mowing wet grass is unavoidable, take steps to minimize damage. Raising the mower deck to its highest setting reduces the volume of wet clippings and lessens the strain on the machine. Walking at a slower pace gives the mower blades more time to process the heavier grass, mitigating the tearing effect.
Ensuring your mower blades are razor-sharp is beneficial in damp conditions, providing the cleanest possible cut under stress. After mowing, immediately rake or disperse any large clumps of wet clippings left on the surface. Removing these clumps prevents smothering the turf and reduces localized moisture that encourages fungal growth.