Improving Your Soil

Much of the soil in Wilson is compacted or eroded, especially in newly developed areas. This is a normal occurrence where large machinery is required to be on the soil. These soils are usually harder to till and have lower productivity. To compensate for this loss, better fertilization, liming, and other management practices should be used. Improving the soil will decrease the amount of surface runoff, increase water absorption and retention, decrease the amount of fertilizer needed, and enhance plant growth.

To improve the soil, start by examining soil compaction and drainage. Corrective measures may be needed to improve drainage. This could include redirecting surface water, installing drainage tile, or incorporating organic material.

In situations of compacted soil or severe eroded soil, it may seem easier to buy topsoil and start over. There are no uniform standards for what is sold as topsoil. New problems may be introduced with the purchased soil, such as weeds or weed seeds, disease organisms, or chemical residuals. Water drainage problems may be created because water cannot move from one layer to another layer of soil of soil.

Adding sand to clay soil seems logical but can actually decrease drainage. The combination of large sand particles and the small clay particles often creates a soil that has properties of concrete with less aeration and drainage. Incorporating peat moss will only increase the moisture-holding capacity, which is already high.

The primary problem with clay soil is excessive water retention, soil compaction, and limited soil air. Never dig, cultivate, have traffic on clay soil that is wet. This will minimize soil compaction.

Increasing soil organic matter improves tillage, as well as water and nutrient holding capacity. Adding organic matter is a continuous process; high organic matter content is difficult to achieve because of our high temperatures and rainfall. The digested and decomposing organic matter helps develop good air-water relationships. In sandy soil, organic material occupies some of the space between the sand grains. This binds them together and increases the water-holding capacity. In clay soil, organic material creates aggregates of soil particles. This allows water to move more rapidly around soil particles, thus increasing the amount of water the soil absorbs.

Organic amendments such as compost, manure, and pine bark are effective and economical. Apply a 3- to 6-inch layer of organic material and incorporate to a depth of 6 to 10 inches. When using straw, leaves, or sawdust you will need to add nitrogen fertilizer while the material is decomposing. Nitrogen is used by soil microbes during decomposition and may become deficient for your intended plants.

The practice of composting organic materials before applying to the soil is one way to avoid tying up soil nitrogen during decomposition. Compost incorporated into the soil increases the organic matter content, improves the physical properties of the soil, and supplies some essential nutrients. Compost can also be applied to the soil surface to conserve moisture, control weeds, reduce erosion, improve appearance, and keep the soil from gaining or losing heat too rapidly.

For more information on improving your soil ,contact the Master Gardeners at 237-0113 on Mondays, Wednesdays or Fridays from 1-3 PM or email at wilsonmastergardener@hotmail.com.

Date Created: 3/31/2004.