Intercropped cover crop agronomy solutions for canola and wheat in the Canadian Prairies

Overview

This research program develops scalable agronomic strategies for intercropping cover crops with canola and spring wheat in the eastern Canadian Prairies, where short growing seasons and post-harvest dry conditions have limited cover crop adoption. By adapting row spacing and plant population recommendations for the cash crops, the work aims to create space for understory cover crops to establish and persist, diversifying monoculture grain rotations, bridging living plant cover into spring and fall windows, reducing fall tillage, and supporting climate resilient food production.

Technical specifications

• Promising cover crop species identified through replicated small plot (2018–2023) and on-farm (2020–2023) trials include Italian ryegrass, red clover, subterranean clover, alfalfa, and phacelia.
• Seeding methods evaluated include drilling cover crops in the same row or in alternating rows with canola and wheat at planting.
• Cash crop canopy management is the next innovation frontier, with prior corn intercropping work showing increased understory persistence and growth when moving from 30 to 60 inch rows.
• Proposed factorial experiment tests two row spacings by three plant populations for canola and wheat intercropped with species specific understory mixtures (red clover and Italian ryegrass with canola; subterranean clover and phacelia with wheat).
• Measurements include early season establishment, late season persistence, fall biomass of the cover crop, crop phenology, tiller number or branching, and grain yield.

Technology readiness level

Initial species and seeding method screening is complete, with multi year small plot and on-farm validation already conducted. The next stage is a replicated small plot field experiment at the University of Manitoba Carman Research Farm during the 2024 season to evaluate row spacing and plant population effects on intercrop performance. Field studies require multiple site years to develop new agronomic recommendations, making continued multi season validation the current priority before broader deployment.