There are several common reasons why your lawn is lumpy. These include heavy foot traffic in certain areas (which causes soil compaction), damage from tires and heavy equipment, lumps from tools, toys, pet waste, and other organic matter getting buried in the lawn, and even improper mowing.
Additionally, how do you smooth out a bumpy lawn?
Use a garden rake to break up raised areas and level them out to the surrounding yard. The best way to smooth out bumpy lawns is a combination of aerating and soil leveling. The more time passes, the less noticeable bumps will be in your lawn; as long as you address the root problems and continue to maintain your lawn.
Moreover, how do you flatten an uneven lawn?
Levelling Shallow Areas
Put a thin layer over the problem area and spread it across evenly. Push the soil down to compact it with your feet or a flat side of a rake. Water the soil a little and leave it to settle. After a few days you can then add grass seed and another light layer of topsoil.