If your lawn has lost its vibrancy and is being overtaken by weeds, the problem may be soil compaction. Compaction generally occurs in areas where there is lots of foot traffic or heavy equipment being moved. Soil structure makes some soils more susceptible than others to compaction. When soil becomes compacted, the particles that make up the soil are closer together, leaving less room for oxygen and water to get to plants' roots.
How to Loosen Compacted Soil Lawn
How do you know if your soil is compacted?
One easy test is the shovel test. If it's difficult to insert a shovel into the ground, then the soil is compacted. Easier still is the walking test. When you walk across your lawn, the ground should feel springy beneath your step. If there's no spring in your step, then compaction is the problem. One dead giveaway is the presence of many weeds in your lawn. Weeds adapt to the adverse conditions of compacted soil in a way that grasses can't. They simply out-compete your lawn for what little air and water filters through the compacted ground.
Treating your lawn for soil compaction is a four-step process of aerating and amending the soil. Follow these steps to return your lawn to a healthy state:
Mow the lawn one-third shorter than usual.
Water deeply at least twice a few days before you plan to aerate.
Aerate the soil using a punch core aerator, not a spike aerator. A punch core aerator actually removes plugs of soil from the ground, leaving a small hole for water and nutrients to enter.
Top-dress the lawn with organic matter and rake it in evenly. This can include a lightweight compost, composted manure, or even coffee grounds. The organic supplements not only provide nutrients to the roots of the lawn, they also encourage earthworms, which loosen the soil and leave castings to feed it even more. With regular watering and mowing, your lawn should regain its usual vigorous appearance in no time.