Grain growers deliberating over whether or not to top up their crops with nitrogen fertiliser have been urged to use a range of tools to make the difficult decision.
While many growers experiencing a favourable season have already topped up with nitrogen, some growers, particularly in the southern agricultural region, are considering an additional application to maintain yield potential.
Department of Agriculture and Food senior development officer Jeremy Lemon said it would be wise for growers to do a budget and assess their paddocks carefully before making the investment.
“It is not a simple decision, as there are so many influencing factors,” Mr Lemon said.
“Every paddock is different and should be considered on an individual basis.
“Growers should consider the paddock’s history, how much nitrogen has gone in already, fertility, organic carbon, plant available water and yield potential – all in context with the forecast for the season.”
Mr Lemon said the timing of the nitrogen application was also crucial.
“For cereals, it is best to apply nitrogen before bolting or stem elongation, before the Z31 Zadok growth stage,” he said.
“Generally, better performing paddocks would respond better than poorer quality paddocks.”
Growers can assess the probability range of yield and likely responses to nitrogen fertiliser by examining Yield Prophet® site reports, while the N-broadacre app, based on DAFWA’s Select Your Nitrogen model, evaluates different nitrogen scenarios.
Meanwhile, DAFWA trials are underway in the Central and Northern Agricultural Regions to help generate better returns from fertiliser investments.
The research, led by DAFWA research officer Dr Craig Scanlan, is part of the More Profit from Crop Nutrition initiative, backed by the Grains Research and Development Corporation.
The project is investigating the effect of lime incorporation on plant responses to nitrogen and phosphorus fertiliser, as well as the effect of soil mixing and other nutrient management strategies.
“The trials will bring together the knowledge that’s needed to help us further understand the impacts of soil pH and soil mixing on nutrient availability,” DAFWA development officer Liam Ryan said.
“This research will help provide growers with a better understanding of how to balance fertiliser expenditure in line with the need to address soil constraints when operating with a limited budget.”
DAFWA officers will discuss the trials at upcoming field days. Check local media for details.
For more information about nitrogen requirements visit agric.wa.gov.au/wheat and follow the links.