Leaf-blades
When the grass is wet, a mower will struggle to cleanly cut the lawn. Mowing when wet can cause the leaf of the grass to tear and become bruised. When the blade is torn rather than cut it can cause more stress to the grass. This results in a deterioration in the plants’ health.
Lawn diseases
Normally when the lawn is mowed, the grasses clippings will be dry and can be scattered throughout the whole lawn. These clippings when left on the lawn can quickly break down and provide the lost nutrients back to the lawn.
However, when the grass is wet, these clippings will stick together forming clumps. These clumps will be damp and will sit on top of your lawn unless they are raked up. This can then restrict the airflow, sunlight, and other nutrients from getting to your lawn. These damp conditions beneath the clippings are perfect for fungal diseases such as brown spot to develop.
These clumps can even get stuck underneath your mower creating a build-up of grass clippings and debris. This overtime can interfere with your mowers blade movement and deterioration of parts. So, if you do happen to mow when there is moisture on the leaf, make sure you wipe out the lawn’s clippings from underneath the mower to help stop the clippings from building up over time.
Uneven cut
After a lawn receives rainfall, the leaf blades of the grass tend to not stand as tall as they usually would. This is because the leaf blade becomes weighed down by the water droplets causing the grass to bend unevenly. As a result of the bent leaf, not all leaf blades will be cut evenly when mowing.
When the lawn dries, the leaf blades which were bent will stand tall again. This will leave an uneven and patchy look to your lawn. So, it is best to wait until the lawn has dried out to get the cleanest, most even cut.
Mowers and wet grass
After rainfall, the soil beneath your lawn can become quite soft.
When mowing, ruts can be formed from the mower moving along the soft surface. This will badly affect your lawn levels and cause significant deviation in the height of your finished grass cut.
When moving a lawnmower over wet soil, there is a chance that the mower could become bogged. After a mower gets stuck, the turf underneath will likely get ripped up, leaving the area bare without any grass, but will also leave big ruts in the soil. As these ruts can be quite large, topsoil may be required to bring the levels back up again.
A wet lawn is a slippery lawn
Mowing the lawn when the grass is wet can become a more labour-intensive task as the mower will require extra force to push through.
The extra effort required to push the mower also causes a potential risk of slipping. This risk of slipping over will become greater if you are mowing on a slope. Slipping over when operating a mower with fast rotating blades will not only give you a fright but can be a significant safety hazard for obvious reasons.
Morning Dew
Unlike rain, morning dew is moisture mostly on the leaf and doesn’t cause excessive amounts of water to be present within the soil. This can mean that mowing while there is still dew present on the leaf, isn’t as much of a concern as mowing after rain. Golf courses and some other facilities have no choice but to mow their grass nice and early when there is dew still on the surface and they manage to keep their grass beautifully manicured. But if you do have the option to wait until the dew has dissipated, then it would be best to do so in the home lawn situation.