GRDC X GGA

Closing the Economic Yield Gap in Grain Legumes in WA

Exploring the Economics of Grain Legumes in a Double Break

Exploring Double-Break Cropping with Legumes Across the Northern Ag Region

With rising weed and pest pressure, worsened by the 2024 season, growers across the Northern Agricultural Region are looking for alternatives to increasingly ineffective chemical controls. A GRDC-funded project, delivered through GGA, is investigating the economic and agronomic potential of double break crop systems featuring grain legumes. Led by Mingenew-Irwin Group (MIG), Greenough Specialty Ag (GSA), Three Springs Farm Innovation Network (3FIN) and Northern Agri Group (NAG), the project aims to determine whether incorporating legumes into rotations can improve weed control, reduce input costs, and boost long-term profitability.

The project includes six small-plot trials across Mingenew, Three Springs, and Northampton, alongside grower case studies to capture real-world experiences. So far, trial sites in Mingenew, Three Springs, and Northampton have been selected, pegged out, and soil sampling completed ahead of seeding. Each of the three locations is set up identically, featuring two trial areas, one on canola stubble and one on legume stubble, to allow consistent comparison across differing rotational backgrounds.

Key data will focus on weed suppression, nitrogen fixation, yield, and economic returns. Findings will be shared through local field days, trial reports, social media, and presentations.

By demonstrating how double-break cropping can build more resilient and profitable farming systems, this project will help close the economic yield gap for legumes and offer a sustainable path forward for growers in the region.


Trials are in the Ground!

Seeding Update

We’re pleased to share that seeding is now complete for the 2025 Double Break Legume Trials across the Northern Agricultural Region.

On the 13th of May, the Northampton trial site was successfully sown, followed by the Mingenew and Three Springs sites on the 14th of May. These trials form part of a GRDC-funded project delivered through GGA and led collaboratively by Mingenew-Irwin Group (MIG), Greenough Specialty Ag (GSA), Three Springs Farm Innovation Network (3FIN), and Northern Agri Group (NAG).

Each location features two trial areas—one on canola stubble and one on legume stubble—to assess how previous rotations influence the performance of double break cropping systems. Trial plots will measure weed suppression, nitrogen fixation, yield performance, and economic outcomes, offering insight into how legumes can play a key role in building more profitable and sustainable rotations.

A big thank you to the DPIRD Geraldton team for their work in seeding and spraying the trials, and to Nick Eyres (GSA) for his assistance on site. Soil sampling is already completed, and we look forward to tracking trial progress as the season unfolds.

Stay tuned for updates via field days, reports, and social media as we gather data to help growers manage weed pressure and close the economic yield gap for legumes.