On-farm bacteriologic culturing (OFBC) provides quick and inexpensive mastitis diagnosis, but commercial adoption of this innovation has been low in Mississippi. We implemented an Extension-led trialing program to identify reasons for producers' lack of OFBC adoption, explore change in producers' knowledge and perceptions of OFBC, and assess the effectiveness of the program relative to OFBC adoption. Most producers were unaware of OFBC initially but identified several benefits after trialing it for 30 days. The methodology for designing and implementing a trialing program based on Rogers's diffusion of innovation framework was effective and could be replicated easily in other contexts.