Interest in growing olives — a high-value specialty crop — is increasing in Oregon. However, research-based information on cultivar selection and production practices for the state is limited. Primary challenges include damage from low winter temperatures and a lack of growing degree days needed to fully ripen fruit.
Oregon State University, with strong support from Oregon’s olive industry, launched the Olea: Olive Research for Oregon project.
Most commercial olive production occurs in regions with warmer, mild winters. To support the emerging industry in Oregon, growers need data on how various olive cultivars respond to winter conditions and whether they can produce quality fruit during the state’s relatively short ripening season. In addition, growing techniques must be adapted to Oregon’s climate.
To address these challenges, Oregon State University, with strong support from Oregon’s olive industry, launched the Olea: Olive Research for Oregon project. The goal is to evaluate as many olive cultivars as possible and identify those best suited to regional growing conditions.
The project sourced cultivars from the U.S. Department of Agriculture Germplasm Repository in Davis, California, as cuttings or small plants. Hundreds of cuttings were propagated for a multi-year, replicated field trial at the OSU North Willamette Research and Extension Center in Aurora.
By July 2021, a 1-acre plot was prepared with drip irrigation and weed mat, and 116 cultivars — totaling 420 plants — were planted, replicated when available. The site is irrigated during the summer and lightly fertilized in early August. Annual data collection includes plant growth, flowering, fruit set, yield, fruit maturation and size, and cold injury. Findings are shared with growers, stakeholders and the public through site visits, classes, media and events.
In 2024, a statewide survey launched to gather information on olive producers and assess industry needs. The Olea team also participated in multiple events, including a poster presentation at the International Olive Sustainability Conference in Davis, California. In May, the Olive Field Day at NWREC drew record attendance, and 100% of respondents said they learned something applicable to their operations.
New collaborations began in 2024, including with Wright State University to evaluate olives’ susceptibility to the emerald ash borer — an invasive pest detected in Oregon in 2022 — and with OSU’s Southern Oregon Research and Extension Center in Central Point to explore olive production as a potential future crop in that region.
The Olea team also traveled to Seville, Spain, to collaborate with researchers at the Instituto de la Grasa and the Cordoba Germplasm Repository. With continued industry support, the Olea project aims to build a strong foundation for successful olive production in Oregon.
