Research by Agriculture Victoria has shown that there are no pasture yield differences when phosphorus fertiliser is applied in summer or autumn1. With this in mind, there are a number of benefits associated with being a step or two ahead when it comes to the timing of your fertiliser application. Things to consider in relation to the early application:
- The movement of water-soluble phosphorus from single superphosphate granules into the soil is virtually complete within 24 hours of application, even when soil conditions are dry and rainfall does not occur. Light dews are enough for the P to move into the soil where it is quite immobile (i.e. will not leach).
- This gives the fertiliser more time to become available to the pasture when it needs it most.
- It also enables you to take advantage of an early seasonal break.
- Early application gives you more management flexibility when it comes to the coordination of transportation, spreading contractors and other services.
- Early application of phosphorus allows for pastures to access fertiliser P, ensuring a rapid uptake following the autumn break.
- Applying phosphorus fertiliser earlier than the traditional autumn application does not increase the likelihood of phosphorus losses through run off, however areas that are prone to storm water may see losses if there is soil movement within 24 hours of application.