Canola profitability as a break crop in the Upper North? (UNF2822)
START
March 15, 2022
FINISH
August 31, 2025
Summary
Three contrasting seasons demonstrated both the strong upside and clear risks of growing canola in the Upper North region. In the wet 2022 season, average canola yields of 2–3.5t/ha and oil levels above 42 per cent delivered margins that often outperformed wheat. The winter of 2023 was dry, and spring frosts reduced average canola yields to 0.4–1.7t/ha. The 2024 season was also dry, with average canola yields of 0.35–1.23t/ha and slimmer margins. Clearfield® types delivered the most consistent risk-adjusted returns across multiple seasons. Results confirm canola is best used strategically, in seasons where early sowing is an option (before approximately 15 May) and in paddocks with weed or disease pressures, rather than as a routine inclusion in rotations.
Background
Canola has long been viewed as a profitable break crop for weed and disease management in the medium to high rainfall zones of SA. However, in the low rainfall Upper North region there are higher seasonal risks associated with growing canola. Early sowing opportunities are limited, occurring only in approximately one year in three in the Upper North, and yield potential can fall quickly in dry starts or frost-prone springs. However, including canola in crop rotations often adds long-term value that is not always captured in single-year gross margins. Wheat following canola commonly yields about 20 per cent more than wheat after wheat, due to strategic disease breaks and opportunities to control grass weeds. This project aimed to provide guidance on the profitability and reliability of different canola technologies compared with wheat, taking into account regional and seasonal variability.
Research Aims
The core objectives of the project were to:
- Compare the profitability and risk of triazine tolerant, Clearfield® and Roundup Ready®/TruFlex® canola systems to wheat across seasons in the Upper North region
- Provide clear guidance on technology choice, sowing opportunity and inputs to improve whole-farm profitability.
In The Field
Trials were conducted over three seasons from 2022 to 2024 at Melrose, Morchard and Wandearah in the Upper North.
Triazine tolerant (TT), Clearfield® (imidazolinone tolerant) and Roundup Ready® (RR)/TruFlex® (glyphosate tolerant) canola technologies were trialled alongside wheat at each site in each season. Treatments reflected commercial practice, including herbicide systems suited to each technology. Gross margins were calculated using seasonal yield, oil content and prevailing grain prices, alongside realistic input costs.
Results
Canola profitability was mainly influenced by seasonal conditions which varied greatly. In 2022 there was good spring rainfall and favourable conditions. In 2023 there was below-average winter rainfall and multiple spring frosts. It was also dry in 2024, with severe heat stress at some sites. Trials were lost due to grazing and crop failure, leaving only Wandearah harvested in 2024. The high variability in seasonal conditions allowed assessment of both upside and downside risks of canola in rotations.
In 2022, average canola yields ranged from 2.0–3.5t/ha, with oil levels above 42 per cent. At several sites, canola margins exceeded wheat, reflecting both yield and price strength. In this favourable year, the higher input systems were justified.
In 2023, average canola yields were 0.4–1.7t/ha. Oil remained high, but gross margins were often lower than wheat. Frost during flowering reduced pod set and increased risk and, in many cases, wheat proved more reliable than canola.
In 2024 at Wandearah, average canola yields ranged from 0.35–1.23t/ha. Despite low yields, the lower input TT system and some Clearfield® treatments still generated positive margins. Wheat yielded 1.37t/ha and only just broke even at $24/ha, highlighting that cereals also struggled in the dry finish in 2024.
Across seasons, Clearfield® lines delivered the most consistent returns when risk was considered. Roundup Ready®/TruFlex® systems provided strong ryegrass control but carry higher risk in seasons where spring moisture is limited or growing windows are short. TT types were suited to lower-input or mixed farming (graze and grain) systems.
Project Participants
Upper North Farming Systems: Jade Rose and Rachel Trengove
AgXtra: Steph Lunn
The Problem
Upper North growers need clearer guidance on when canola is a profitable break crop option compared with wheat
The research
Three years of on-farm trials compared TT, Clearfield® and RR/TruFlex® canola systems with wheat across seasons
More information
Rachel Trengove, Upper North Farming Systems
T: 0438 452 003
E: [email protected]
Value for Growers
The project demonstrated both the potential and the limitations of canola in the Upper North region. Canola has a place in rotations, but as a tactical tool aligned with seasonal outlook and paddock conditions, rather than as a default crop. Growers are most likely to benefit if the season is conducive to early sowing by mid-May, if paddocks have high grass weed or disease pressure, or if input costs are matched to realistic seasonal yield potential. Yield increases in wheat following canola also contribute to improved whole-farm profitability.
Clearfield® systems appear to offer a balanced risk-return profile, while the higher input costs of Roundup Ready®/TruFlex® systems may be justified where grass weed pressure is high and spring rainfall forecasts are favourable. TT systems suit lower-cost input strategies or mixed farming systems where the graze and grain option can add a valuable buffer.
