Sum16-32 NPK on Oats, Williams


Part of a trial series to assess how wheat responds to nitrogen (N), Phosphorus (P) and Potassium (K) fertilizer applications under different conditions, soil P stores and soil Phosphorus Buffer Index PBI across the Wheatbelt.

For further details contact your local Area Manager or the Summit Research Team

Table 1: Soil Analysis
Fig 1: Yield and Protein responses
Fig 2: Responses to N & P +- K


  • Application of P and N significantly increased yield in this trial and the addition of K had less of an impact.
  • Maximum yield was seen at N 120 kg/ha, P 18 kg/ha with K 25 kg/ha providing a minimal increase.
  • Adequate P nutrition is imperative, promoting early growth and setting up the crop to utilise N efficiently and gain maximum value from in-season N fertiliser application.
  • Soil testing will assist in fertiliser decisions for P and K and continual local research trials will build a foundation of robust and validated data to support these decisions.