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 and type of fertilizer that is needed. A soil test also measures soil pH, humic matter and exchangeable acidity. For example, these analyses indicate whether lime is needed and, if so, how much to apply.
Why Do You Need A Soil Test?
Soil testing improves plant growth by providing the recommendations specific for the soil tested. It allows IFD to prescribe and provide what is actually needed for the desired crop to be at its best.
When growers guess about the need and amount of lime or fertilizers, too little or too much is likely to be applied. By using a soil test report, the grower does not need to guess. The exact requirements are met.
For Example: When applying too much lime, soil pH may rise above the needed level. This causes nutrients such as iron, manganese, boron, copper and zinc to become less available to plants, and production suffers. It is also common to see homeowners purchase one bag of lime when they purchase one bag of fertilizer. Based on an average lawn size of 5000 square feet, one bag of fertilizer may be enough. Applying one bag of lime over 5000 square feet, however, will have little effect on soil pH.
Thus we need to –
Diagnose whether there is too little or too much of a nutrient
Encourage the environmental quality of the items being added
When gardeners apply only as much fertilizer as is necessary, nutrient runoff of surface or ground water is minimized and natural resources are conserved and t he results are much better.This saves money that might otherwise be spent on unneeded lime, fertilizers and other elements.
One good example is that growers of flue-cured tobacco often routinely apply phosphorus. In areas where soil levels are high in phosphorus a good soil test could save these farmers up to $60 per acre.