The lime needed per acre for a pasture should be assessed after determining the pH level of the soil and the type of grass that will be grown on the pasture. Patchy grass and the presence of acid-loving weeds can be indicators of a lime deficiency; however, the only accurate method of determining the amount of lime needed per acre is to perform a soil test. The amount of lime needed per acre is calculated by assessing the pH level of the soil and determining how much the pH should be increased to maintain the type of grass on your pasture.
Things You'll Need
Soil test kit
Paper and pencil
Test the pH level of your pasture by obtaining a soil test kit from your local cooperative extension office.
Collect soil samples from several different locations in the pasture to be limed. Numerous samples must be taken from a number of areas in the field and tested individually as the pH level can vary throughout your pasture. Multiple soil samples will provide an overall average of the pH level of your pasture.
Draw a map of your pasture using paper and pencil and record the areas where the samples were taken. Recording the sample locations will allow you to apply the correct amount of lime required to the appropriate areas of your pasture.
Package soil tests as instructed and return the kit to your local extension office for testing.
Evaluate your soil test results to assess the pH level of your pasture.
Determine what type of grass you will be growing on the land being tested. The optimum pH level for most crops is between pH 6.0 and pH 7.0; however, the appropriate pH level for your pasture will depend on your crop. For example, bermudagrass only requires a pH level of 5.5.
Discuss your pH level and pasture grass with your extension service agent to determine the correct amount of lime needed per acre. If you are not able to talk to your extension agent, you can use the Agricultural Lime Association's table for Lime Applications to determine the appropriate amount of lime per acre.
Typically, the soil test results will indicate how much lime is needed per acre to raise the pH to 6.8. If the soil has an extremely low pH level and requires a large amount of lime, the application can be spread out by applying one-third of the required lime each year for three years. This will allow you to spread out of the cost of the lime application over three years.
When applying lime to the surface of the soil, apply no more than 2 1/2 tons per acre during the year. If the lime is worked into the soil, up to 4 tons may be added per acre.