Coordinating agronomist: Yolaine Filion
Organization: Club d’Encadrement Technique Pommes de Terre
Practices: Cover crops, nitrogen management
Barrier: Potatoes are heavy feeders, and under- or over-applying nitrogen can affect plant health, yield and quality. In colder regions with shorter growing seasons, uncertainty about nitrogen credits from leguminous cover crops makes it difficult for potato growers to confidently adjust synthetic nitrogen fertilizer rates.
Description: This replicated split-plot trial will compare a legume cover crop (forage peas) seeded after canola harvest with a no cover crop control. Three post-emergence nitrogen (N) rate treatments will be applied: the grower’s standard nitrogen rate and two reduced rates (15 kg N/ha and 30kg of N/ha below standard). Cover crop biomass, soil and petiole nitrate levels and potato yield and tuber quality will help quantify nitrogen credits, while an economic analysis will evaluate the feasibility of adjusting synthetic fertilizer rates accordingly.