Exploring soil, leaf and fruits nutrient ranges and relationships in sweet cherry orchards in Okanagan Valley, Canada

The Okanagan Valley, renowned for its sweet cherry production, contributes a significant 94.5% to Canada’s total output.
This prominence has led to vast export opportunities, increasing the demand for superior quality fruit.
A two-year study was undertaken to investigate the relationship between soil, leaf, and fruit nutrient concentrations in the valley’s ‘Staccato’ cherry orchards.
Across the valley, 30 orchards with ‘Staccato’ cherries on Mazzard rootstock were selected.
The sampling process included soil (0-30 cm depth, spring 2021), leaves (collected four weeks before harvest), and fruits (harvested in 2021 and 2022). The study primarily aimed at analyzing soil for available nutrients, leaves for their total nutrient content, and fruits for both nutrient composition and quality.
The results were then compared with the optimal nutrient ranges identified in the literature, employing correlations and regression analyses to assess the interplay between various parameters.
The findings indicated that certain orchards exhibited sub-optimal levels of calcium (Ca), iron (Fe), and boron (B) in the soil, alongside concentrations of nitrate, phosphorous (P), zinc (Zn), manganese (Mn), copper (Cu), and sodium (Na) that exceeded optimal levels.
Correspondingly, leaf samples from some orchards revealed insufficient levels of Ca and Fe, along with excessive P, Zn, Mn, and B. A significant correlation was observed between spring soil nitrate and leaf nitrogen (N), C/N ratio, and Ca/N ratio (R²=0.2-0.4), where higher soil nitrate corresponded with increased leaf N, a lower leaf C/N ratio, and a lower leaf Ca/N ratio.
Additionally, a positive relationship was noted between soil K/Mg ratio and leaf Fe (R²=0.3). Adversely, soil nitrate and B were linked to decreased fruit Ca/N and B levels, respectively (R²=0.2-0.3), and fruit Mn concentration was negatively affected by soil pH (R²=0.4-0.6). Notably, positive correlations emerged between leaf and fruit N, Mn, and B (R²=0.2-0.8), with fruit firmness impacted by fruit Ca/N (R²=0.4-0.6) which is correlated with leaf N (R²=0.2-0.5). This research underscores the importance of establishing region-specific optimal nutrient ranges for sweet cherries, fostering sustainable orchard management and the production of high-quality fruit suitable for storage and export.

X International Symposium on Plant Nutrition of Fruit Crops

M. Sharifi, B. Wolk, H. Xu, G. Krahn, S. Slamka

fruit quality, nutrients relationships, soil available nutrients, ‘Staccato’

https://doi.org/10.17660/ActaHortic.2025.1432.29