Tailored Fertilizer Rates for Fresh and Frozen Maine Wild Blueberry Producers

Commodities

• Fruits: berries (blueberries)

Practices

• Crop Production: application rate management, fertilizers, nutrient management
• Education and Training: decision support system, demonstration, extension, farmer to farmer, mentoring, networking, on-farm/ranch research, technical assistance, workshop
• Soil Management: nutrient mineralization, organic matter, soil analysis
• Sustainable Communities: community development, local and regional food systems, partnerships

The 46,370 acres of commercial wild (lowbush) blueberries in Maine grow on a two year production cycle, in acidic soil conditions and contain more plant genetic variability than the highbush blueberry production system. Fresh and frozen market destinations have different quality standards and therefore farmers use different harvest methods depending on the destination of the fruit. This project proposes to educate producers on existing nutrient knowledge within this unique production system and that wild blueberry plants themselves could be grown specifically for each market avenue. Wild blueberry stem height and fruit load are the first plant factors that could be adjusted using different rates of nitrogen and potassium when applied granularly. As the fresh packed sector of the wild blueberry industry grows, calcium may be a critical nutrient for fresh fruit quality on a crop that has not been bred for storability. This project builds upon an organic nutrient and weed management project that was funded by SARE from 2019-2022 (Project # LNE19-374), a one year calcium study funded by a Specialty Crop Block grant, and leverages a one year Wild Blueberry Commission funded project to begin this work in 2024. Since the first SARE project, there has been a push from fertilizer company representatives and some Maine wild blueberry growers to use foliar fertilizers as the main source of nitrogen, which the scientific community does not support. Farmers are now demanding a longer term, more complete study of conventional fertilizer applied at different rates to help them make scientifically informed fertilizer decisions. The two main objectives of this project are to 1) create improved nutrient management outreach materials and deliver that research-based knowledge to all wild blueberry farmers regardless of size, management practices, race, or gender, and 2) fine-tune through applied research the N, K, and Ca fertilizer necessary to produce high quality berries for fresh and frozen end markets. 

Ten farms who manage a total of 20,000 acres adopt more precise granular fertilizer applications on a field by field basis, resulting in 500 lbs/acre ($285/acre) of fruit gained or $40/acre savings from fertilizer costs.