A damaged lawn is an unsightly problem, but it does not have to be a permanent one. Many possible causes of a damaged lawn exist, including dehydration due to drought, soil erosion due to heavy rains, constant foot traffic over certain patches of the lawn and frost damage from sub-zero temperatures. When repairing lawn damage keep in mind that not all grasses are the same; your lawn will look best if you repair the damaged patch with a type of grass similar in colour and style to the original. Bring a small patch of your old grass with you to a nursery to determine the best variety.
Determine the exact causes of damage to your lawn. This will help you when researching methods of fixing the underlying issues in the future.
Dig up the dead or damaged grass from the soil using a backhoe or shovel. Leave neat edges around the area. Do not be afraid to remove a bit of healthy grass surrounding the patch of dying grass.
Turn over the dirt in the patch using a shovel or gardening fork. Mix in a bit of fertiliser and topsoil. Water the patch of refreshed dirt until it is damp.
Spread an even layer of grass seed over the patch of newly turned soil. Cover the seed with 1/4 inch or less of topsoil; too much and the grass will not be able to germinate properly. Lightly pat the patch down using the bottom of your backhoe.
Lightly cover the new grass with a thin layer of hay if your lawn had been damaged previously by heavy rain. This will protect the growing seeds from harsh weather conditions. A light covering of peat moss is also effective at protecting the young grass sprouts.
Water regularly to keep the area damp. Once the seeds begin to sprout use more water, but space the waterings out more in order to encourage the root system to grow deeper into the soil. You can begin to treat it as just another part of your lawn once the grass has reached a height comparable to the rest of your lawn.
Treat your growing grass with respect and care, taking care not to over-water the plot (or let it dry out for that matter). Grass is typically stronger than other types of plants but it still takes a bit of nurturing to ensure that the patch grows back strong and healthy.
Be careful not to step on the newly seeded patches of lawn until they have established a health root system. This typically takes a few weeks after the grass looks lush. Prematurely disturbing a patch of recovering lawn can slow down the new growth or even cause it to die, forcing you to repair the same section all over again.