To investigate responses to phosphorus and potassium in wheat.

• The early crop vigour results in this trial demonstrates the need to apply fresh phosphorus to crops at seeding to ensure good plant shoot and root growth during the early stages of crop growth.
• There was no difference observed between potassium drilled with the seed or topdressed immediately after sowing.  Good rainfall conditions early in the season may have rapidly moved the topdressed potassium into the root zone of the crop therefore overcoming any differences due to placement.  Subsoil testing for potassium may be important to determine the size of the soil potassium pool.