New results to mitigate risks for lentils

New results indicate the application of gypsum on crops could be a game-changer for lentil growers on the Lower Eyre Peninsula.

Plagued by waterlogging in many of the traditional lentil growing areas last season, advice based on recent research is set to remove some of the risks associated with growing lentils, promoting a more stable and higher-yielding crop option.

AIR EP Executive Officer Naomi Scholz said the research created the most interest at its recent Lower EP Ag Expo, with farmers keen to hear about their options.

“Waterlogging of lentils impacted most who grew them on the Lower EP last year, so it was timely to examine and look at options to mitigate the risk,” Ms Scholz said.

EPAG Research Agronomist Andrew Ware carried out the research, sampling six sites across the Lower EP, collecting soil and plant samples from zones with good, moderate and poor growth.

“While the problem isn’t exactly new, the wet season in 2022 helped make it visual in a way we haven’t seen before,” he said.

“The patterns of waterlogging did not match the topography, as waterlogging damage occurred in a mosaic across the landscape, rather than just in the low-lying areas.”

Results showed that soil from areas of poor lentil growth had higher levels of sodicity. Sodic soils are those with a sodium absorption ration (SAR) greater than 15.

“Excessive boron or sodic subsoil within the crop root zone can cause plant death and severely limit lentil yields, so these results make sense,” he said.

“I suspect that traditionally growers have looked at areas of lentils dying out in above-rainfall seasons and called it waterlogging, which it is. However, understanding it’s being driven by sodicity (which slows the soils ability to drain) may be new to some growers and allow them to fix it through the application of gypsum.”

While lentils only made up about 2 per cent of crops grown in the region last season, they are a higher value pulse crop, and can offer good returns to growers.

Going forward, Mr Ware suggested conducting soil tests in the areas where poor growth has been experienced to confirm the cause and seek advice on a gypsum application plan, if warranted.

“Gypsum is the most practical solution to overcoming sodicity issues. The rate, timing and number of applications will depend on the severity of issues, so growers should seek specific advice for their situation,” he said.

Ms Scholz said while lentils were still the best break crop financially, they came with a higher risk.

“If this risk can be lowered, it will make a more attractive and viable option, which could lead to higher yields,” she said.

For more information, contract AIR EP Executive Officer Naomi Scholz on 0428 540 670 or EPAG Research Andrew Ware on 0427 884 272.