Soil amendments have been around for many years. Their use has historically been primarily in various sport field applications, including golf course greens, rooftop gardens, soccer pitches, and football fields, but soil amendments have also been used in projects including the landscaping of roadsides, parks and private and municipal landscape projects such as museums, and botanical gardens. So what exactly are soil amendments?
A soil amendment is a component that can be added to soil to enhance the soil’s ability to grow and sustain healthy turf or plants, and to reduce water usage – pretty important in drought affected areas lately. Unlike fertilizers, the primary use of soil amendments is not for nutrient value to the soil per se; rather, soil amendments are used mainly to improve the porosity of the soil. While the primary use of soil amendments is not to add nutrients to the soil, some soil amendments do contain desirable concentrations of magnesium, potassium, and iron. Also, it is necessary to add fertilizers to the soil seasonally or cyclically on a repeated basis as they are used up, whereas a soil amendment will continue to function almost indefinitely, although it might require more than one addition to reach the desired concentration.
There are several potential benefits to adding a soil amendment, but the primary benefits imparted to the soil are two-fold:
1) To minimize soil compaction. For example, golf greens may suffer from heavy traffic, particularly on weekends or during tournament play. The addition of an effective soil amendment will minimize compaction of the soil and will reduce stress to the turf. Similarly, a soccer pitch or football field also suffers from compaction. The addition of an effective soil amendment will greatly reduce stress to the sports turf.
2) To act as a water reservoir, both in terms of holding water and also releasing water to the plant’s roots. Both diatomaceous earth (DE) and clays have high porosity (ranging from about 70% for many calcined clays to about 84% for calcined DE).
3) Some soil amendments, zeolites, in particular, claim to increase the Cation Exchange Capacity of the soil; however, this is usually not a reason for adding a soil amendment to the soil, as most soils have an adequate CEC value due to organic content in the soil (i.e., peat moss).
Most soil amendments fall into one of three mineralogical categories: calcined diatomaceous earth (DE) such as Axis DE Regular or Axis DE Fine, calcined clay, such as Axis Ceramic, or zeolites. All have high porosities, but pore size directly influences the ease with which a plant root can “pull” water from the soil (Plant Available Water). The smaller the pore size, the higher the pressure with which the soil holds the water, and the higher the pressure the soil holds the water, the more difficult it is for the plant roots to pull the water from the soil and make the water (and nutrients contained in it) available to the plant roots.
Calcined DE and Clay such as all natural Axis DE or Axis Ceramic have the highest porosity and the largest pore spaces, which significantly improves the plant available water leading to good plant, landscaping, sports turf and golf course health and growth. You can water more deeply and less often and also make the most of any natural rainfall. Our customers have documented water savings of 30% and more by using Axis on their lawns.
