November 28, 2001 | By: Laura Skillman

Fall is a good time to sample soils to determine nutrient needs for the coming year's crops. The University of Kentucky College of Agriculture has two soil testing facilities that can provide farmers with professional test results.

Fall is a good time to have the testing done in order to plan ahead, said Frank Sikora, UK soil test coordinator. Phosphorus and potassium can be fall-applied leaving one less thing to do during the busy spring.

Fall testing is especially important for lime application. It takes as much as six months for lime to provide the maximum benefit after being applied, he said.

The labs - one in Lexington and one at the UK Research and Education Center in Princeton - test thousands of samples each year to aid farmers and homeowners in determining their fertilizer needs. Since 1988, the two labs have handled between 43,000 and 60,000 samples annually.

Tests at the lab are performed on media utilized for plant growth operations such as soils, water for tobacco float-beds, greenhouse media, and animal waste. Chemical analyses and recommendations from the University of Kentucky Agricultural Testing Labs are specifically made for Kentucky conditions. Nutrient needs and fertilizer responses are determined by research conducted through UK on crops and soils in Kentucky.

The Lexington lab performs the routine soil test (pH, buffer pH, P, K, Ca, Mg, Zn) and non-routine tests which include boron, organic matter, pH and nutrients in greenhouse media used for various horticultural crops, pH and nutrients in water used for irrigation and nutrient solution purposes, nutrients in animal waste used for land application, and potential acidity in mine spoil. The Princeton lab performs the routine soil test.

Soil testing at the UK labs is performed for agriculture, home, lawn and garden, and commercial horticulture.

A professional staff at the soils lab prepares the solution to be tested, and tests are conducted by trained chemists, Sikora said. The labs use an extract called Mehlich III to determine the nutrient levels in soils. It is becoming increasingly important that this extract is used because federal nutrient management plans specify that it is to be used, he said.

Soil testing is not like having your cholesterol level checked, Sikora said. In that case, you don't have to ask what procedure was used. But soil testing is not as precise and there are different methods being used to determine nutrient levels in soils.

Farmers who may be comparing last year's test results to this year need to be aware that different labs use different testing methods as well as different units. UK lists levels in pounds per acre while other results may be listed in parts per million. So, farmers need to make sure they are comparing similar testing methods from one year to the next, wherever the testing is done.

For more information on the UK soil testing program contact your local Cooperative Extension Service office.


Frank Sikora, (859) 257-2785 ext. 257