Due to high fertiliser pricing, every cost on the farm has needed justification even more than usual. Natalie Wood, agronomy operations manager at Yara, spoke out in winter on this topic and advised growers to review their final N rate in spring so that they can fully take the up-to-date crop status and economics into account. The time has now come.
“Current fertiliser prices mean that applying nitrogen still has a high cost,” said Ms Wood. “However, wheat and oilseed prices are also high; this indicates that the economic optimum has shifted back to more normal levels.”
To put this into hard figures, the economic optimum for N is now approximately 190-200kg/ha. At the start of the year, when crop prices were lower, this was closer to 160-180kg/ha.
With this in mind, what is the best strategy for determining final N rates? Naturally, it’s crucial that any applications meet the expected growth response and avoid excess N leaching. Optimum rates will ensure everything applied is fully utilised by the plant.
“This means that it is now worth switching tactics and fully pushing for yields,” she said. “Generally, crops look like they have good potential. Of course, your final dressing rate will depend on what you’ve already applied and the crop type. For example, if you are growing milling wheat, you will need an additional 40kgN/ha for increasing protein levels.”
This extra N can be added to the final application. However, trial work carried out by Yara has revealed that when the N is applied as a separate dressing at growth stage 51 for solid or milky ripe for liquid, it can increase protein levels by up to 1%.
“The best course of action this spring is choosing a quality granular fertiliser that can spread to the required distance,” added Ms Wood “Ideally, the product should contain N in both the ammonium and nitrate forms, so that the nutrients are immediately available for plant growth.”
“As always, consider the unique circumstances of your farm and what your crop needs. Choosing the right product will help achieve the results you’re after. Now is the time to be pushing for yields and benefit from the groundwork you laid in winter.”
