Mixed method evaluation of factors influencing the adoption of organic participatory guarantee system certification among Vietnamese vegetable farmers

In markets where vegetables are commonly cultivated with heavy use of synthetic pesticides, it is particularly important for consumers to be able to identify genuine organic produce. Organic Participatory Guarantee Systems (PGS) certification offers smallholder farmers an affordable way to build trust among consumers and secure premium prices for their organic produce. In Vietnam, the demand for vegetables with no, or low, pesticide residues is growing. The attractiveness of PGS certification should increase accordingly, but the number of organic PGS certified farmers in Vietnam are stagnating or even decreasing. The aim of this study is to explain this paradox by investigating the factors that influence the adoption of organic PGS certification among Vietnamese vegetable farmers. We follow a mixed methods approach, combining a qualitative analysis of farmer interviews (n = 62) and a quantitative analysis of a farm survey data (n = 434) using a sample selection model that estimates adoption contingent on farmers’ awareness of PGS certification. Drawing on the Unified Theory of Acceptance and Use of Technology, we found that social relationships and positive attitudes towards farming and the environment drive the adoption of organic PGS. Barriers include insufficient knowledge of organic farming techniques, labour shortages, and ageing farmers. At the systemic level, support by (non-)governmental institutions facilitates adoption, but challenges such as lower yields and limited access to premium markets remain. To promote organic PGS among Vietnamese vegetable farmers, efforts should focus on disseminating organic farming techniques that boost yields, alleviate labour demands, and ensure secure markets for premium-priced organic vegetables.