Nutrient Management: Fertilizing with Compost and/or Manure
alternative practice names:
Farmers can use manure and composted manure to meet their crop nutrient demands. Both manure and compost are abundant sources of nitrogen, phosphorus, potassium, and many other essential plant nutrients. When used correctly, these sources can replace commercial fertilizers in crop production while contributing to a reduced crop carbon footprint, improved farm economics, and positively impacting agronomic production. Manure and/or compost likely will not replace all crop nutrient needs. Unlike purchased fertilizer, the nutrient ratio of manure cannot be easily changed without additional equipment, so manure sampling and up-to-date nutrient management plans should be in place.
When used, in what regions in the U.S. is the practice found:
Northwest, West, Upper Midwest, Southwest, Northeast, Southeast
FARM SIZE
When used, typically found on farms of the following sizes:
All Sizes

Practice Benefits
Cost savings: Applying manure and compost can reduce the need for commercial fertilizers. These organic amendments provide essential nutrients, often at a lower cost than synthetic alternatives.
Enhanced crop yields: When properly managed, manure and compost serve as slow-release fertilizers, gradually breaking down and supplying nutrients throughout the growing season.
Improved soil health: Manure and compost improve soil structure by increasing organic matter content, which enhances soil aeration, water retention, and nutrient-holding capacity. Additionally, these amendments stimulate microbial activity, which contributes to long-term soil health.

Implementation Insights
Site-specific or Farm-specific requirements

In most cases, there are no specific site or farm requirements.
Required Capital Expenditures (CapEx)

Application equipment: Properly distributing manure requires a significant investment in specialized equipment for transporting and spreading. This equipment includes manure spreaders, slurry tanks, pumps, agitators, and application tools that ensure even distribution of nutrients across the fields. Some farmers opt to hire custom operators instead of making this sort of capital investment.
Required Operational Expenditures (OpEx)

Sampling: Effective use of manure as fertilizer requires understanding its nutrient content to determine the appropriate application rate for crops. Regular manure sampling is essential because nutrient concentrations can vary significantly between farms and even from year to year. Annual testing of manure and compost helps farmers accurately assess nutrient availability and the potential replacement value of commercial fertilizers. Consistent sampling ensures that the correct amount of nutrients is applied, reducing the risk of over-application and nutrient loss while maximizing crop uptake.
Transport: Transporting liquid and slurry manure over long distances can be prohibitively expensive, often making commercial fertilizer a more cost-effective option for distant fields. To reduce transport costs, farmers can adopt strategies like separating and drying manure solids or using dewatering technologies to reduce the volume and weight of manure, lowering transportation costs and improving nutrient application efficiency. Alternatively, farms can utilize dragline systems or fertigation to transport manure at a lower cost.
Implementation Considerations

Calculating nitrogen availability: Manure contains nitrogen in both inorganic forms, which are immediately available to plants, and organic forms, which are stored in organic matter and released slowly as they decompose and mineralize. The nitrogen content in manure and compost can vary significantly throughout the year and across different years, necessitating regular measurement. The nitrogen mineralization rate from manure depends on factors such as temperature, moisture, and microbial activity, with warmer and moist conditions accelerating the process. Generally, a significant portion of the nitrogen in manure becomes plant-available within the first year, while the rest is released more gradually over subsequent years. Accurately determining the amount of nitrogen being applied and its availability at key times in plant growth is complex, leading many farmers to supplement with additional commercial nitrogen as a precaution. See Nutrient Management: Accounting For Nitrogen Credits from Legumes and Manure.
Phosphorus and potassium build-up: When manure is applied to meet nitrogen needs, excess phosphorus and sometimes potassium are often applied. Over time, this can lead to a build-up of these nutrients in the soil. To manage this, farmers should consider applying manure based on phosphorus requirements rather than nitrogen.
Incorporation: Some states, counties, and municipalities require manure to be incorporated into the soil under specific conditions or times of the year to reduce nutrient runoff. While this practice helps protect water quality, it can increase costs and may conflict with reduced tillage or no-till farming systems.
Setbacks: Regulations in many areas set specific distances, or setbacks, where manure cannot be applied, such as near wellheads, waterways, or areas with concentrated flow. These setback areas often need to be fertilized with commercial nitrogen, requiring additional planning, equipment, and field passes.
Excess salt build-up: In regions with low rainfall, the risk of salt build-up from repeated manure applications is higher. Composted manure typically has a higher salt concentration due to the composting process, and frequent or large applications (e.g., 20 tons per acre) can cause salt injury to plants, especially in areas without enough precipitation to leach the salts from the soil.
Financial Considerations and Revenue Streams
FINANCIAL RESOURCES, TOOLS, AND CASE STUDIES
Additional Resources
Article: Save Money and Get Cleaner Water by Correctly Utilizing Manure (University of Wisconsin-Madison)
Factsheet: Nitrogen Credits from Manure (Cornell University)
Guide: Determining Crop Available Nutrients from Manure (University of Nebraska-Lincoln)
Report: Using Manure as a Fertilizer for Crop Production (University of Missouri)
Website: Nutrient Management Cirriculum (Cornell University)

Environmental Impacts
REDUCES FARM GREENHOUSE GAS EMISSION
The greenhouse gas (GHG) emissions associated with fertilization depend on multiple factors, including production methods, transport distances, application techniques, and environmental conditions. In general, using manure instead of commercial fertilizers to supply crop nutrients can reduce a farm’s overall GHG footprint. The use of manure in lieu of commercial fertilizer avoids the significant GHG emissions associated with the production of synthetic fertilizers. However, the actual GHG savings can vary based on factors like manure management practices (e.g., storage and handling), application methods, and farm-specific conditions, such as soil type and climate. A life cycle analysis (LCA) or process-based model is typically used to comprehensively assess the GHG impacts of different fertilization practices, including both synthetic fertilizers and organic alternatives like manure and compost.

Alignment with FARM Program
FARM Environmental Stewardship (ES) V2-V3 Alignment
FARM ES Version 2 and Version 3 ask if the farm has a nutrient management plan (NMP), if it is maintained and implemented. FARM ES Version 3 also includes an optional crop module, allowing users to enter their unique management practices including fertilizer and manure application.
Contents
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
We're always eager to update the website with the latest research, implementation insights, financial case studies, and emerging practices. Use the link above to share your insights.
Farmers can use manure and composted manure to meet their crop nutrient demands. Both manure and compost are abundant sources of nitrogen, phosphorus, potassium, and many other essential plant nutrients. When used correctly, these sources can replace commercial fertilizers in crop production while contributing to a reduced crop carbon footprint, improved farm economics, and positively impacting agronomic production. Manure and/or compost likely will not replace all crop nutrient needs. Unlike purchased fertilizer, the nutrient ratio of manure cannot be easily changed without additional equipment, so manure sampling and up-to-date nutrient management plans should be in place.
Practices and technologies
Nutrient Management: Fertilizing with Compost and/or Manure
alternative practice name: