Sum15-02 Potassium rate, source and timing, Dandaragan

AIM:

To assess the value of different sources of potassium on growth and yield of wheat when applied by banding and topdressing at seeding time or topdressing after emergence.

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

Table 1: Soil Analysis
Fig 1: Yield response to different K treatments
Fig 2: Soureces and timing



Fig 3: Yield Response to K

CONCLUSIONS

Mace wheat responded to K application at the site, but the response and yield was less than anticipated due to growing season rainfall being 200 mL below average.

Highest Gross Margin occurred where 50K kg/ha was applied drilled at seeding.

On similar soils in the area, applications of K are recommended at 30 kg/ha to optimise wheat yields or higher if K rundown is expected or determined by soil testing.