Manage nitrogen fertiliser use through the 4Rs (Right Source, Right Rate, Right Time, and Right Place) to optimise nutrient management, improve crop yields, reduce nutrient losses to the environment, and enhance the sustainability of agriculture.
What Can I Do?
Not all the nitrogen fertiliser is taken up by crops and some of it runs into waterways or is broken down by microbes in the soil, releasing nitrous oxide, a potent greenhouse gas, into the atmosphere. Fertilisers are also energy intensive to produce and lead to water pollution and reduced soil health.
The 4Rs – “Right Source, Right Rate, Right Time, and Right Place,” represent a framework for precise nutrient management to optimise crop yield, reduce environmental impact, and enhance sustainability.
Right Source: Select the appropriate type of fertiliser that matches the nutrient needs of your crops. For nitrogen, this could involve choosing between urea, ammonium nitrate, or other nitrogen sources. For other nutrients, it might involve selecting the right form of phosphate or potash, depending on your soil conditions.
Right Rate: Determine the correct amount of each nutrient to apply based on the specific requirements of your crops and the nutrient levels in your soil. This ensures you provide enough nutrients for healthy plant growth without overapplication, which can lead to environmental issues.
Right Time: Apply the fertiliser at the time when the crops can most effectively take up the nutrients. For example, nitrogen should be applied when the crop needs it the most during its growth stages. Phosphorus and potassium may have different timing requirements.
Right Place: Apply fertilisers precisely where the crops can access them. This minimises waste and reduces the risk of nutrient runoff or leaching into the environment. Proper placement can vary depending on the nutrient and the method of application.
For additional information refer to Nutrient Best Management Practices for beef, sheep and dairy grazing enterprises in south-west Western Australia.