Please contact our Customer Centre for pricing information 0800 100 123


N 0.0
P 9.3
K 0.0
S 15.0
Mg 0.0
Ca 23.0
  • Rebateable
  • Blend of some Fertmark products

Product Description

RPR 15S varies with rock types from pink to brown or black particles, with yellow crystals of elemental sulphur.​

Why Use RPR 15S

Slow release phosphate fertiliser suitable for maintenance applications

Suits hill and high country farms with good rainfall and low soil pH

Contains slow release phosphate, calcium and elemental sulphur

Caution When Mixing

While Reactive Phosphate Rock on its own generally mixes well with other products, the Sulphur Super 30 component of RPR 15S it is not compatible with the following:

Urea or Magnesium Oxide

Sulphur Super 30 can be compatible with the following under certain circumstances:

Flexi-N (magnesium coated Urea), Ammonium Sulphate Granular, Potassium Nitrate, Ammonium Nitrate, Mono Ammonium Phosphate (MAP), Cropmaster DAP or Calcium Ammonium Nitrate (CAN)

Segregation may occur when mixed with product with differences of particle size.

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To order this product contact the customer centre and place your order.

0800 100 123


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Product Sizes available

  • Bulk

Delivery Options

  • Pickup


Important Information


    A slow release phosphate fertiliser suitable for maintenance applications.

    Suits hill and high country farms with good rainfall and low soil pH.

    A 50:50 blend of reactive phosphate rock and sulphur super 30 containing slow release phosphate, calcium and elemental sulphur.

    Requires soil acids to dissolve the rock phosphate to plant available forms.

    RPR 15S is a slow release fertiliser which may have environmental benefits where high rainfall and surface runoff occurs subsequent to fertiliser application. However, once the P and S components are dissolved in soil solution the fate of these nutrients are no different than for soluble P and S fertilisers. Reactive Phosphate Rock requires soil acids to dissolve the rock phosphate to plant available forms. The lower the soil pH and the finer the particles the quicker this reaction takes place. Elemental S is slow release sulphur as it requires the action of Thiobacillus bacteria in the soil to convert the elemental S to sulphate S and the speed of this dissolution is moisture and temperature dependent as well as faster for finer particles.

  • USES

    RPR 15S is not suitable for capital fertiliser application, but is best suited for maintenance applications. It is most suited to hill and high country farms at maintenance soil fertility levels where rainfall is good to high and soil pH levels below optimum.


    Spreading rates for RPR 15S vary greatly depending on phosphate and sulphur requirement; other important factors include climate, farm type. productivity and soil type.

    Soil testing and fertiliser plans are available to ensure you use the right product at the correct rate - please call our Customer Centre or your account manager for information.

    Due to the fine particle size of this product special care is needed to achieve an even spread. Spreader calibration should be carefully checked and the bout width will probably need to be reduced.

    As with most solid fertilisers, RPR 15S can be stored over a season as long as it is kept in a cool, dry, well-ventilated area.