Columbia — The University of MU Extension Soil and Plant Testing Laboratory is moving to a new soil nutrient extraction method that will provide faster results and more complete nutrient analysis while keeping testing costs lower.
The laboratory is adopting the Mehlich-3 method, now considered the industry standard for soil testing, said lab director Rasel Parvej. Before making the switch, the lab conducted extensive testing to ensure the new method produces results that match and correlate with the long-used procedures previously employed by MU Extension.
“This careful evaluation ensures that soil test results remain reliable and consistent for farmers, gardeners and agricultural service providers,” Parvej said.
The Mehlich-3 method improves laboratory efficiency and allows for turnaround times typically within three business days, depending on sample volume. It also makes it possible to analyze more nutrients in a single test, reducing the need for multiple extractions and helping keep overall costs down.
Mehlich-3 measures plant-available phosphorus, potassium, calcium, magnesium, sulfur, sodium, zinc, iron, manganese, copper, boron and aluminum, giving users a more complete picture of soil fertility across a wide range of soil types.
Parvej said the method is especially helpful for phosphorus testing. The older Bray-1 test works best in acidic soils but is less reliable in neutral to high-pH or calcareous soils. Mehlich- 3 performs well across a broader range of soil conditions, making it better suited to the wide variety of soils found across the state.
Under the new system, MU’s complete soil test package will be priced at $15 per sample. Volume discounts are available for single orders: • more than 100 samples, 10 percent • more than 500 samples, 15 percent • more than 1,000 samples, 20 percent
Those submitting more than 5,000 samples per year should contact the lab at soiltestingservices@ missouri. edu or 573-882-0623.
The complete soil test package includes soil pH (salt), neutralizable acidity and organic matter; phosphorus, potassium, calcium, magnesium, sulfur, sodium, zinc, manganese, iron, copper and boron; and cation exchange capacity. Soil pH (water), buffer pH, base saturation, cation exchange capacity-based soil texture and extractable aluminum will also be reported soon.
Parvej said the new system will allow MU Extension to build a comprehensive statewide nutrient database. That will improve soil test calibration and fertilizer and lime recommendations, help track nutrient trends by region over time, and provide stronger, research-based guidance for both farm profitability and environmental stewardship. The Soil and Plant Testing Laboratory analyzes soil, plant tissue, grain, forage, water, manure, compost and greenhouse media. Its mission is to provide high-quality testing and unbiased, research-based recommendations that support sound nutrient management.
The fee-based services are available to farmers, homeowners, vegetable and fruit growers, lawn and landscape professionals, golf course managers, consultants, researchers and government agencies.
The laboratory’s services include soil fertility analysis, fertilizer and lime recommendations, specialized tests for nutrient management and environmental concerns, potting-mix analysis for nurseries, plant tissue testing, compost and manure analysis, and water testing for domestic, irrigation, poultry and livestock use.
More information is available at muext.us/ SoilPlantLab.
