Soil pH is the amount of acid or alkaline in a soil. Most plants require a neutral pH or a soil that is balanced. Typically a soil's pH can range from 4.0, which is extremely acid, up to 9.0, which is very alkaline. A balanced soil is 7.0, which is equivalent to pure water. The best way to test a soil's pH value is to conduct a soil test. Your local agricultural extension service offers these tests for little to no cost.
Conduct the soil test for the area you want to balance the pH level. Typically the soil is taken from a number of locations from around the field or garden site. The soil is thoroughly mixed, allowed to dry and a sample is sent to the extension service. Generally it takes up to 4 weeks to receive the test results back from the laboratory.
Read the test results and consult the extension service if any information is not clear. You can cause a larger problem by adding too much lime to reduce the acid level in the soil. In the same manner, you can also add too much nitrogen-based fertilizer to lower a high alkaline soil.
Broadcast the correct amount of the pH balancing agent over the soil. Generally this is described as pounds per acre. In a smaller garden plot, it will be described as pounds per 1,000 square feet. Agricultural lime will be added to reduce the acid level in a soil and raise the pH level. A nitrogen fertilizer, typically an ammonia base, will be used to lower a high pH level.
Use some type of cultivation method to work the balancing agent into the soil. A large field will require the use of a tractor that can pull a mechanical cultivator over the field. The tines of the cultivator will mix the agent into the soil. Use a roto tiller to work in small areas such as garden plots or flowerbeds. Generally the application of any balancing agent is performed in late winter to early spring prior to any planting of crops or plants.
Allow the material, added to the location, to sit for one year. Take another soil test and wait for the results. Balancing the pH level in soil takes time. In some cases, it is part of a routine soil management program.