ASHS 2025 Conference

Many direct-market farmers in western Washington are interested in sweetpotatoes (Ipomoea batatas) for crop rotations, to increase farm sales, offer a culturally relevant crop to consumers, and adapt to climate change. We conducted research station and on-farm trials in 2023, 2024, and 2025 with the goal of testing cultivars, developing production guidelines, and introducing sweetpotato as a new crop for the region. The trials were a partnership between WSU researchers, who led the research station trials, and WSU Extension, who led the on-farm trials. Research station trials provided yield and wireworm resistance data for nine cultivars and breeding lines, and on-farm trials introduced sweetpotato to farmers in the region. On-farm trial participants were provided with slips or roots of three sweetpotato cultivars and a production guide. In 2023, 20 farmers across three counties signed up to participate, 15 farmers planted trials (75% of signups), 11 farmers returned surveys with some data (73% of planted trials), and 5 farmers provided complete data (33% of planted trials). Due to varying management practices and incomplete responses, 2023 on-farm trial data were largely unusable for evaluating yield or wireworm resistance. In 2024, 33 farmers across nine counties signed up to participate, 29 farmers planted trials (88% of signups), 25 farmers returned surveys and/or had data collected by a WSU Extension Field Assistant (89% of planted trials), and 20 farmers provided complete data (71% of planted trials). Hiring a part-time field assistant in 2024 who visited farms and collected data increased farmer response rate and data completeness. Yet, on-farm trial yield and wireworm resistance data still were not fully usable due to inconsistencies in how data were collected, and lack of adherence to production guidelines. In 2025, we redesigned on-farm trial data surveys to focus on farmers’ perceptions regarding suitability of sweetpotato production and marketability for their farm. Participating farmers are uniquely well-suited to answer these qualitative questions, which will assess if sweetpotato has been successfully introduced in the region. In all years of the project, online growing classes, in-person field days, and farm walks proved useful for introducing sweetpotato to new farmers in the region. Visits to on-farm trial locations proved an important avenue of offering support to farmers experimenting with sweetpotato. Completed surveys and conversations with on-farm trial participants provided valuable feedback that was incorporated into our sweetpotato production guide, and expanded and improved our on-line resources including several short production videos.