For aerating compacted grass soil, which material blend is most effective?

• A. Clay and mulch
• B. Clay
• C. Sand and organic material
• D. Hard packed soil

Answer: (C)

When soil is compacted, the goal is to restore pore spaces so air, water, and roots can move through easily. A blend of sand and organic material does this best because coarse sand creates larger air-filled pores that improve drainage and root penetration, while organic matter helps bind soil particles into stable aggregates, boosting structure, moisture movement, and microbial activity. Together, they rebuild a looser, more breathable soil profile after aeration. Clay on its own tends to compact further and reduce porosity, and hard-packed soil is the problem, not a remedy. A mix of sand with organic material provides the right balance of immediate pore space and long-term soil health to improve a compacted lawn.