What is a Soil Test?
A soil test is a process by which elements (phosphorus, potassium, calcium, magnesium, sodium, sulfur, manganese, copper and zinc) are chemically removed from the soil and measured for their "plant available" content within the sample. The quantity of available nutrients in the sample determines the amount of fertilizer that is recommended. A soil test also measures soil pH, humic matter and exchangeable acidity. These analyses indicate whether lime is needed and, if so, how much to apply.
How much soil is needed for a soil test?
Top Notch Inspections recommends sampling about 0.5 pound. This amount should be enough to represent the area being tested. The boxes used for submitting samples have a "fill line" that shows the amount of soil needed.
What is a soil test extractant?
An extractant is a mixture of various chemical reagents dissolved in water. It removes plant-available nutrients from the soil and dissolves them in a liquid phase. Most extractants can remove phosphorus, potassium, calcium, magnesium, manganese, zinc and copper from a sample.
How often should a soil be tested?
As a rule, test sandy-textured soils every 2 to 3 years and clay soils every 3 to 4 years. However, if any problems occur at any time contact, TopNotch Inspections or visit the New Jersey Department of Agriculture website.
What does the pH measure?
Soil pH indicates how acid or basic a soil is. It is a logarithmic function of the hydrogen ion concentration. A pH of 6.0 is ten times more acid than a pH of 7.0; a pH of 5.0 is 100 times more acid than a pH of 7.0, and so on. A pH of 7.0 is neutral; below 7.0, the soil is acid; above 7.0, the soil is basic. For example, battery acid has a very low pH (<3.0); household ammonia is basic and has a high pH (>10.0).
What is the most desirable pH for growing plants?
It depends on the plant.
| Plant Type | Optimum Soil pH |
|---|---|
| Azalea, rhododendron, camellia, mountain laurel | 5.0–5.5 |
| Most shrubs and shade trees | 6.0 |
| Fescue, bermudagrass, zoysia, St. Augustinegrass | 6.0–6.5 |
| Centipedegrass | 5.5 |
| Rose | 6.5 |
| Berries and most fruit trees, except blueberries | 6.0–6.5 |
| Most vegetable and field crops | 6.0–6.5 |
| Tomato | 6.5 |
What is lime and how does it benefit the soil and plant growth?
Lime is any substance with the capability of neutralizing soil acidity. Most soils contain appreciable amounts of acidic components - hydrogen (H+) and aluminum (Al+++) that can be toxic to plants. Indeed, lime is the "anti-acid" for soils.
No soil amendment provides as many benefits as lime. Lime raises soil pH, providing a more favorable environment for microorganisms. Dolomitic lime provides the major portion of calcium and magnesium required for plant growth. Furthermore, plants utilize applied fertilizers more efficiently on soils that are properly limed.
How often should lime be applied?
Apply lime only when recommended by a soil test. Some soils need to be limed every 2 to 3 years, others every 3 to 4 years. In general, sandy-textured soils need to be limed more frequently than clays because sandy soils are more subject to pH changes caused by leaching and fertilizer treatments.
Ideally, lime should be applied and mixed into the soil before a crop is planted. However, if the need is great, lime can be applied even when plants are already in place. Unlike fertilizers, lime can be spread over growing crops without damaging the crop. When lime has been applied as recommended, do not apply more without taking another soil test.
Top Notch Inspections, Inc. tests many other factors in your soil. The inspector will be happy to answer any questions you may have. All of your "soil properties" will be listed in the Soil Testing report.