By Blake Jackson
With fertilizer prices remaining unpredictable and nitrogen and phosphorus products still costly, farmers are looking for practical ways to reduce nutrient expenses.
According to Penn State Extension, fall is an ideal time to evaluate the economic value of manure as crops are harvested, soil tests are completed, manure applications are planned, and fertilizer purchases are considered.
Manure can provide more than a disposal solution for livestock operations. When properly managed, it supplies nitrogen (N), phosphorus (P), potassium (K), organic matter, and other nutrients. The challenge is determining how much those nutrients are actually worth compared with commercial fertilizers.
Penn State Extension’s Manure N-P-K Economic Value Calculator helps farmers make that comparison. The tool considers three key factors: manure nutrient content, crop nutrient requirements based on soil tests and expected yields, and current commercial fertilizer prices.
It estimates the value of N, P, and K that manure can provide, including both longer-term nutrient value and the amount that can replace fertilizer needed for the following crop.
For example, fertilizer prices in September 2026 were approximately $925 per ton for diammonium phosphate (DAP) and $495 per ton for potash.
After accounting for the nitrogen contribution from DAP, the calculator estimates values of about $0.73 per pound of P₂O₅ and $0.41 per pound of K₂O.
Using those figures, 5,000 gallons per acre of representative dairy manure could provide roughly $99 in P and K value.
The same amount of representative swine manure could provide about $133, while two tons per acre of representative poultry litter could supply approximately $101 in P and K value.
Transportation and application expenses must also be included. Manure with significant nutrient value may not be economical if hauling and spreading costs exceed the fertilizer savings. Local manure can be particularly useful when livestock and crop farms are located nearby.
Nitrogen can add substantial value, but its availability is less predictable than P and K. Application timing, incorporation, rainfall, and the manure ammonium and organic nitrogen content all affect how much becomes available to crops.
Penn State Extension emphasizes that soil testing is essential. Manure should provide nutrients that a crop actually needs; applying excess phosphorus or potassium can create agronomic and environmental concerns.
By combining soil-test recommendations, manure analysis, and current fertilizer prices, farmers can use the Penn State Extension calculator to determine whether nearby manure offers a practical way to reduce fertilizer costs.
Photo Credit: gettyimages-magicxeon
Categories: Pennsylvania, Crops, Livestock, Beef Cattle, Dairy Cattle