A long-term project in China has demonstrated that multistakeholder collaboration and equal dialogue with smallholder farmers can effectively promote sustainable farming practices. The Science and Technology Backyard (STB) platform was initially used to transfer knowledge to smallholder farmers, but it faced challenges in scaling up sustainable technologies. To address this, the project expanded and upgraded the STB platform to STB 2.0, emphasizing equal dialogue, multistakeholder collaboration, and long-term investment. Through field trials in three regions of the North China Plain over five years, the study found that technologies co-created with farmers were more easily accepted and increased crop yields and nitrogen productivity by 7.2% and 28.1% in wheat, and 11.4% and 27.0% in maize. A "one-stop" multistakeholder program involving local governments, enterprises, universities, and farmers was developed, which proved more effective than traditional extension methods in promoting sustainable practices. This program significantly improved environmental and economic outcomes. The study highlights the importance of integrating farmers' feedback and addressing their socioeconomic challenges to achieve sustainable smallholder agriculture. The STB 2.0 platform provides a model for technology scale-up in smallholder farming, emphasizing collaboration and long-term investment. The findings suggest that equal dialogue and multistakeholder collaboration are crucial for promoting sustainable practices among smallholder farmers globally.A long-term project in China has demonstrated that multistakeholder collaboration and equal dialogue with smallholder farmers can effectively promote sustainable farming practices. The Science and Technology Backyard (STB) platform was initially used to transfer knowledge to smallholder farmers, but it faced challenges in scaling up sustainable technologies. To address this, the project expanded and upgraded the STB platform to STB 2.0, emphasizing equal dialogue, multistakeholder collaboration, and long-term investment. Through field trials in three regions of the North China Plain over five years, the study found that technologies co-created with farmers were more easily accepted and increased crop yields and nitrogen productivity by 7.2% and 28.1% in wheat, and 11.4% and 27.0% in maize. A "one-stop" multistakeholder program involving local governments, enterprises, universities, and farmers was developed, which proved more effective than traditional extension methods in promoting sustainable practices. This program significantly improved environmental and economic outcomes. The study highlights the importance of integrating farmers' feedback and addressing their socioeconomic challenges to achieve sustainable smallholder agriculture. The STB 2.0 platform provides a model for technology scale-up in smallholder farming, emphasizing collaboration and long-term investment. The findings suggest that equal dialogue and multistakeholder collaboration are crucial for promoting sustainable practices among smallholder farmers globally.