Cranberry, a fruit crop native to North America, has found a thriving production hub in Southern Chile. While the USA and Canada lead global production, Chile stands out in the Southern Hemisphere, achieving remarkable yields and demonstrating significant potential for future growth. Crucial to this success is effective nutrient management, as cranberries are cultivated in sandy soils with limited clay content. This research investigates the critical nutritional requirements of cranberry plants in Southern Chilean agroecosystems, correlating soil and plant tissue analyses across different phenological stages. We aim to establish optimal nutrient levels for maximizing yield and quality. Our study, conducted in collaboration with Cran Chile from 2018 to 2020, monitored 'Pilgrim' cranberry plants across three parcels under four different fertilization strategies. We tracked the foliar variation of ten essential nutrients, comparing plants grown in soils with varying fertility levels and aligning these data with growing degree days (GDD) to model nutrient dynamics. Key findings reveal distinct patterns in nutrient concentration over time: Nitrogen, phosphorus, and potassium levels decreased, while magnesium, sulfur, iron, and zinc followed a third-degree polynomial curve. Calcium, boron, and manganese concentrations increased throughout the season. These nutrient dynamics provide a broader window for tissue sampling and are essential for establishing critical nutrient concentration benchmarks for cranberry plants. Furthermore, this study examines the phenology of cranberry in Southern Chile, comparing it to established models from the USA and Canada. We utilized GDD-based functions to model phenological stages, revealing a notable difference: cranberry development in Chile occurs earlier than in the Northern Hemisphere. This advancement is likely attributed to the milder winters in Chile, which result in less pronounced dormancy compared to the colder climates of the USA and Canada. In conclusion, this research provides valuable insights into the nutritional needs and phenological behavior of cranberry plants in Southern Chile. By understanding these dynamics, we can optimize cultivation practices, ensuring sustainable and high-yield cranberry production in the region.
