Composts rely on biological processes for enhancing soil nutrition. WSU has conducted extensive research on the use of compost as a soil amendment and source of nutrients. This work points out the need to understand the composition of a particular product (compost is highly variable) and how it acts in a soil, especially in terms of potential nutrient release. As an already-stabilized material, compost may be more useful for improving long-term soil quality and nutrient supply than as an immediate source of nutrients for crops. In addition, active areas of work include composting as a strategy for managing municipal and mixed waste streams, the combination of composting with other waste management processes (e.g. co-composting with biochar), and the potential for composting to break down or retain organic chemical contaminants (e.g. hormones, antibiotics).

Featured Publications

Evaluating Compost Application for Soil Carbon Sequestration on Agricultural Land and Compost Buy-Back Programs in Washington State (PDF)

Ball, K.R., M.P. Brady, I.C. Burke, D.P. Collins, K.M. Hills, C.E. Kruger, B. Stone, E.L. Taylor, and G.G. Yorgey. Evaluating Compost Application for Soil Carbon Sequestration on Agricultural Land and Compost Buy-Back Programs in Washington State. Report to the Washington State Legislature. Center for Sustaining Agriculture & Natural Resources, Washington State University, Wenatchee, WA

Washington Soil Health Initiative Roadmap

Hills, K. & C. Benedict (Eds.) 2021. Washington Soil Health Initiative Roadmap. Washington State University, Pullman WA. October 2021.

Soil Amendments (PDF)

Yorgey, G., W. Pan, R. Awale, S. Machado, A. Bary. 2017. Chapter 7 In Yorgey, G. and C. Kruger, eds. Advances in Dryland Production Systems in the Pacific Northwest. Washington State University Extension, Pullman, WA.

Composts and Nutrient Management

The WSU Puyallup Research Center faculty have conducted extensive work on compost, manure and biosolids. This website provides information on yard waste and food waste composts, clopyralid, calculating bulk density, nutrient management for organic systems and compost facility operator training events. The site has links to the Compost Mix Calculator the Organic Fertilizer Calculator and […]

On-Farm Composting of Large Animal Mortalities

Price, C. and L. Carpenter-Boggs. WSU Extension Bulletin EB2021E. 2008. Composting can be a safe and effective method for disposing of on-farm mortalities when the correct procedures are followed and the system is managed well. This bulletin provides the necessary information for large animal producers in Washington State to start and maintain a safe and […]

Additional Publications

WSU Compost Facility

WSU operates a full scale composting facility on the Pullman campus to recycle organic waste, while providing teaching and research opportunities.

Home Gardening: Compost

A peer-reviewed site for Extension Master Gardeners and homeowners to learn about home gardening, including compost.

Compost Images

An archive of digital photos of various aspects of agricultural composting and compost use to assist agricultural professionals and others in their education programs. Produced as part of the Compost Education and Resources for Western Agriculture project with funding from the Western SARE Program.

Browse all Compost Publications

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