To avoid breaking an ankle while strolling through your yard, holes must be filled in — particularly several ones. Whether they are caused by animals or settling, the remedy would be exactly the same; filling the hole with quality soil to encourage the growth of new grass roots for a healthy lawn.
Dig under the grass in long bob with the spade and set the sod aside; this is reused after the hole is filled, if the grass seems to be healthy.
Mix the potting soil with compost or sand in equal parts in the bucket or wheelbarrow with the trowel.
Put spadefuls of the soil mix to the hole. To fight settling, bring the soil mix about an inch over the surrounding soil.
Put the removed sod back above the filled hole and then pat it in place. Water the sod extensively to establish root growth in the new soil.
Fertilize the lawn to encourage healthy root growth. Natural fertilizers — like compost or grass clippings — may provide the ideal combination of potassium or nitrogen to the soil without needing a soil test. Simply sprinkle it on the sod or new grass seedling to provide nutrients.