Help for Compacted Soil

What Is Soil Compaction?

• Soil compaction occurs when the soil undergoes continuous impact by rainfall, sprinkler irrigation, foot traffic, construction activities or other actions. Compacted soil looses the "pores," or empty spaces between soil particles where oxygen, moisture and nutrients rest. Because compacted soil is difficult to correct, implement measures to prevent it by adding amendments, limiting foot traffic and providing rainwater drainage as early as possible.

Testing For Soil Compaction

• A simple test for determining if your soil is compacted is to push a metal rod 6 to 8 inches deep into the soil at various points. If it does not go into this depth easily, your soil is compacted. Another method is the ribbon test. Gather a handful of soil and roll it into the size of a ping-pong ball. Then, squeeze it tightly in your fist to make a ribbon. If the ribbon lengthens to about 3 1/2 inches long and doesn't break, the soil has up to 50 percent clay in it and requires treatment.

Tilling Soil

• Cultivating the soil helps to break apart compaction and introduces spaces within the soil structure. This in itself will help aerate the soil and make it more water absorbent. Do not cultivate overly wet or overly dry soils, however, as this can destroy the soil structure.

Aerating Soil

• Aerating the soil at various points along its surface can help to add pores for water retention and air circulation. Use either mechanical equipment or manual methods to create holes in the soil at 2-inch intervals.

Adding Soil Amendments

• One solution to the problem of soil compaction is to add organic soil amendments. These materials add empty spaces to soil where air and water can rest. Organic amendments such as compost, manures and pine bark are more effective and more economical for this purpose than other types of amendments, according to North Carolina State University horticulturalist Erv Evans. Add a 3- to 6-inch layer of the amendment onto the surface and work into the soil thoroughly.

Soil Replacement

• When soil is badly compacted, it may be more cost effective to simply replace it with new topsoil. Ensure that you know the composition of the topsoil you are purchasing and whether it is free of weeds, chemical residues or large amounts of clay or sand that will not help your drainage issues. Do not simply lay a new layer of topsoil over compacted soil. Roots cannot grow through the compacted layer, according to the Colorado State University site.