Assessing Appropriate Subsidy Rates for Compost Application to Washington Farms (coming soon)

This report analyzes the first two rounds of Washington State Department of Agriculture’s Compost Reimbursement Program, which reimburses farms for up to 50% of compost application costs. The authors examine whether financial incentives can increase agricultural compost use, support organic waste diversion from landfills, reduce greenhouse gas emissions, and help farmers understand the benefits and costs of compost applications. The report finds that the program reached many farms already using compost, especially organic tree fruit farms, while also helping first-time users try compost on 40% of participating fields. It also finds that transportation distance strongly affects costs, with transportation costs exceeding compost purchase costs when farms are more than roughly 68 miles from a compost facility. The report estimates greenhouse gas savings at about $53 to $114 per metric ton of CO2e avoided, based on reimbursement costs. It recommends considering program design options such as maintaining or adjusting caps, exploring tiered subsidy rates, supporting on-farm experimental applications, and improving outreach to small, beginning, and low-resource farms.