Adjusting Pastureland Soil pH for Spring Fertilizer Applications
In order to have a healthy and vigorous stand of bahia or bermudagrass, Spring fertilizer applications are made. These application rates are calculated by first understanding how much of a given nutrient is present in the soil and available to plants. Soil samples can be collected and submitted for an understanding of its nutrient content at a given point in time. Along with nutrient information, the soil test also provides the pH of the soil. Why is soil pH important? The chart below explains the relationship between soil pH and nutrient availability to plants in soil.
Most plants have an optimum range of soil pH that they prefer to live in (area within the green box). It is at this pH that the plant can most easily take in available nutrients from the soil. For bahia and bermudagrass, the optimum pH is somewhere around 6.5. Florida soils, because of the high population of pine trees, tend to have a lower pH (around 4.0 – 5.0). Also, because of the limestone bedrock in Florida, there are areas of soil that have extremely high pH (> 8.0). The addition of lime can help increase pH and the addition of sulfur can help lower it. However, did you know that it takes between four to six months for soil to adjust pH after the addition of lime to increase pH or sulfur to decrease it? That means that soil tests should be conducted NOW (November) to evaluate the pH. If lime is needed then it should also be applied ASAP so that by March/April when it is time for fertilizer applications, the soil will have had time to adjust its pH.
Right now is the time to be taking soil samples in your pasture. Click on the Shovel below to visit the University of Florida’s Soils Lab website for more information on soil sampling, submission, and cost.