Feeding the world’s growing population

New Zealand’s reputation as a quality food producer is growing.

Optimising food production

Over the next 50 years farmers around the world will need to produce more food than has been grown over the past 10,000 years.

Best use from a limited resource

Fertiliser helps farmers produce food efficiently by replenishing the soil. But fertiliser needs to be used responsibly.

Responsible and sustainable nutrient management

The Fertiliser Association invests in research and tools to ensure farm profitability while minimising nutrient losses to the environment.

The Fertiliser Association of New Zealand promotes and encourages responsible and scientifically-based nutrient management.

Read more

Best management practices for phosphorus (P) fertiliser use


Best management practices

Choice of fertiliser

  • Soluble phosphate fertiliser is used where:
    • rapid plant response is required
    • soil P levels are required to be increased rapidly
    • plants are actively growing
    • there is a low risk of runoff
  • Slow release phosphate fertiliser is used when:
    • there is a high risk of runoff and/or
    • a rapid plant response is not required and/or
    • soil P levels are adequate and/or
    • soil pH is less than 6.0 and annual rainfall is greater than 800mm

Rate of fertiliser application

  • Nutrient application rates are determined using some or all of the following factors:
    • soil and plant tissue analysis
    • nutrient budgets (including any effluent and/or feed imported to the block)
    • crop type, yield/quality/stocking rate targets
    • the need for capital or maintenance applications
    • previous crop and fertiliser history
    • soil moisture conditions and expected future weather patterns
    • local knowledge
  • The amount of phosphate applied per application is limited:
    • when high rainfall is anticipated or irrigation is planned
    • on very sandy soils, particularly for soluble phosphate fertilisers
    • when slope is greater than 25º, and/or pasture is less than 25mm high (approx. 1000 kg DM/ha)
    • during winter
  • Soluble phosphate fertiliser must be applied in split dressings if the single application rate would exceed 100 kg P/ha.
    Phosphate is applied in proportion to other nutrients, according to plant requirements. (Adding excessive P when other elements limit crop or pasture growth is inefficient and could lead to P losses.)

Application technique

  • Application equipment used is suitable for the conditions and fertiliser type.
    Only Spreadmark accredited spreading companies (experienced operators and calibrated equipment) should be used
  • GPS and GIS technology is used for precise application and for a digital record of fertiliser application locations.
  • Non-target application of fertiliser is avoided by:
    • using fertiliser with larger particle sizes and few or no fine particles (aerial application)
    • application techniques that direct or specifically place the fertiliser appropriately
    • application in bands when sowing crops or pasture seed
    • applying fertiliser only when any wind is blowing away from sensitive areas
    • apply fertiliser only under agreed conditions (e.g. wind speed of less than 15 km/h)

Frequency of application

  • Nutrient availability is matched to plant demand, particularly for soluble P products and liquids.
  • Split applications are used where the single application rate would exceed 100 kg P/ha for soluble P or liquid fertiliser.

Timing of application

  • Pasture is at least 25mm high (approx. 1000 kg DM/ha) before P is applied.
  • Phosphate fertiliser is not applied after a dry (drought) period until sufficient regrowth has occurred after rain.
  • P fertiliser is not applied when the soil is saturated

Fertiliser use and management measures

  • P fertiliser is not applied to severely compacted soils. Soil aeration techniques are used on such soils before fertiliser application.
  • To avoid fluoride toxicity to stock, pastures top-dressed with P fertiliser are not grazed for 21 days or until 25mm of rain has fallen.
  • Only phosphate fertilisers which comply with the industry limit of 280mg of cadmium per kg of P are used.
  • Vegetated riparian buffer strips of sufficient width (10m - adjust for slope) to filter any run-off are maintained adjacent to all waterways.

The Fertiliser Association of New Zealand and Dairy NZ funded development of the Nutrient Management Adviser Certification Programme (NMACP). This industry-wide certification aims to ensure that advisers have the learning, experience and capability to give sound nutrient advice.

Find out more

30 September 2021

We recently submitted evidence to the Environment Select Committee on proposals to ban nitrogen fertiliser.

11 August 2021

Creating tools to assist farmers to make the right choice on nutrient management is a long and sometimes expensive process. The Fertiliser Association is committed to a journey of enabling New Zealand farmers to meet their goals for profitability and heightened environmental responsibility.

Sign up for our Newsletter

Stay in touch with the latest fertiliser industry news and research

Sign up

MoST Content Management V3.0.7781