How to Stop a Lawn From Dying

Avoid cutting grass to short to keep it healthy, as over-trimming can hasten the death of a lawn. When grass is cut too short, it becomes weak and susceptible to diseases and bugs. Taller grass shades its roots, keeping them from drying out in the sun. Extra length also helps grass retain water. Toxics Info recommends keeping fescue 3 to 4 inches tall and bermuda and zyosia grasses at least 3/4 inch high.

Water the lawn early in the morning in order to keep it safe from disease and allow the grass to obtain the maximum benefit. Watering the lawn around five in the morning allows the grass to dry before sundown. Wet grass is more susceptible to fungus, which is most active at night. Also, water the lawn deeply in order to strengthen its roots and encourage growth, as a light watering can result in weak, shallow roots.

Fertilize the lawn with the nutrients and minerals it needs. Lawns are able to obtain much of what they need from the soil; however, they often require potassium, nitrogen and phosphorus in greater amounts, so use a fertilizer high in these elements. Phosphorus helps roots to grow strong, nitrogen also promotes growth and makes grass green while potassium regulates the plant's physiological processes. To help grass survive winter, fertilize in the fall, giving it a boost before the cold arrives.

Dethatch the lawn to remove old, dead buildup and help the earth underneath it receive sunlight and water. Thatch, which is matted sections of dead or dying grass, gathers in clumps and smothers the soil beneath. Use a rake to remove sections of thatch by hand, or if it's more than 1/2 inch thick, use a special de-thatching machine. If thatch buildup is a continuous problem, use a hollow-timed aerator to oxygenate the soil and improve its quality.

Mow during the winter as well. Waiting too long between mowings makes grass grow tall and thin, not low and dense as desired. As grass still grows in the winter, albeit more slowly, it still needs trimming. If the weather is reasonably mild and dry, mow the lawn and continue doing so as the weather allows.