Summer Cropping

Our summer cropping fertiliser range has a variety of fertilisers that ensure critical nutrients such as nitrogen, phosphorus, potassium, sulfur and trace elements are supplied throughout any crops life-cycle.

Impact Fertilisers is dedicated to supplying growers with quality fertilisers and plant nutrition support every season.



  • Agromaster is a controlled release fertiliser product, offering improved efficiencies. 
  • Nitrogen is released gradually, throughout the growth stages of your crop.
  • There are two versions of Agromaster, both with a three month release period. The tropical version is tailored to suit Northern Queensland growing conditions. 
ProductsRelease PeriodN%P%K%
Agromaster3 months45--
Agromaster Tropical3 months44--

Tunza Crop

  • Good nitrogen maintenance is essential for reaching target yields and protein.
  • Phosphorus is essential at planting time for stimulating early root formation and growth.
  • Sulphur is critical for nitrogen fixation and chlorophyll formation.
Tunza Crop 1514.612.111.60.9
Tunza Crop 1818.416.26.00.3
Tunza Crop 1918.813.19.40.3

Zinc Cote 

  • Each Zinc Cote granule has a zinc coating that provides zinc with a granular Nitrogen base.
  • Ideal for use on soils that require zinc maintenance applications or in correcting a zinc deficiency.
  • Provides the opportunity to add a new timing window to apply zinc i.e. when spreading Nitrogen fertiliser.
  • Gives growers an agronomically sound option to soil apply effective levels of zinc where low rates of Phosphorous are applied.
Silver N45      1.0


  • A high performance, premium cropping fertiliser for use on winter and summer crops.
  • The product is created by adding zinc to MAP during the granulation process with zinc delivered in every granule.
  • Improves plant uptake of zinc by the even distribution of zinc at the root zone.

Tunza Cotton

  • A pre-plant or planting fertiliser designed for cotton crop.
  • Provides an all-around base planting mix for high yielding cotton crops.
  • This formulation results in an even distribution of nutrient along the row as zinc is contained in every Nitrogen and Phosphorus granule.
  • Potassium is included to meet the crop’s requirement for Potassium during flowering and boll fill.
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Tunza K Cotton Zn0.6%5.512.
Tunza P Cotton Zn0.7%7.015.315.01.40.7
Tunza Zn Cotton Zn1.8%6.711.

Summer Pro

  • Nitrogen is the critical nutrient for protein production.
  • Sulphur is closely related to the nitrogen in the production of protein within the plant.
Summer Pro 301529.915.0
Summer Pro 331233.112.0
Summer Pro 361035.79.6
Summer Pro 370837.57.9
Summer Pro 400540.35.3
Summer Pro 400639.66.0
Summer Pro 410540.84.8

Tunza Rice

Tunza Rice Zn0.7%
Tunza Rice Zn1.5%12.615.38.41.5