Lush green grass relies on nutrients such as water and sunlight, as well as proper care practices. For the most vibrant, thickest lawn, you need to train the grass. Forcing the roots to grow deeper and longer, in search of water, will result in a well-established root system. The better and healthier the roots, the thicker the grass crops become. This also lessens the chance of disease and weeds. To break grass so it grows thicker, focus on key practices.
Water the grass deeply once a week. Let the water run over the lawn for 20 minutes, so it penetrates the roots. This amounts to 1 to 2 inches of water, which will give the roots what they need to grow deeper and stronger.
Mow the lawn shorter. Typically, the recommended mowing height is 3 inches. Cutting the grass shorter and closer to the ground will make for a thicker, healthier lawn. Stay on top of the mowing because you never want to cut more than one-third of the leaf blade at any one time. If you keep it short and don't let it grow tall in between mowing, it will be healthier. The grass will fight for sunlight, causing the roots to go deeper for water.
Keep the grass clippings on the lawn after mowing. They will give the soil nutrients because they act as a natural compost after the blades break down.
Create air pockets in the soil to improve circulation among the roots. Aerate the lawn every three months, using a machine aerator or lawn aerator shoes. Taking the soil cores out will also let more water deep into the ground and prevent weeds, thatching and disease.