Nitrogen cap


2 min read

Timeframe rules Permitted activity Resource consent Gaining resource consent Nitrogen reporting

Nitrogen cap rules control the application of synthetic nitrogen fertiliser based on how land areas connect. If your farm's milking platform and support block are contiguous, the cap applies to both as one. The rules began on 01 July 2021. You can use synthetic nitrogen up to 190kg/ha/year on each hectare of land. Going beyond this limit regularly needs resource consent, with specific conditions for approval. All dairy farmers must report their nitrogen use every year by 31 July. It's essential to keep records of areas, nitrogen types, rates, and dates of application since 01 July 2021 for yearly council reports. If you're considering how to manage or reduce nitrogen usage on your farm, seek advice.

The nitrogen cap rules relating to the application of synthetic nitrogen fertiliser are calculated based on contiguous landholdings.

For example, if a farm has a milking platform and separate support block the nitrogen cap is applies separately but if the milking platform and support block are part of the same land area (i.e., adjoining) the nitrogen cap applies to both conjointly.

Timeframes – when the nitrogen cap rules apply

  • 01 July 2021 - N-cap rules commence
  • 31 July 2022 - first report of the previous season N usage due to Council - reporting delayed
  • 29 August 2022 - The national reporting tool became available for entering and submitting a nitrogen use report

Permitted activity

Synthetic nitrogen may be applied as a permitted activity at a rate of no more than 190kg/ha/year to each hectare of land not used to grow annual forage crops and as an average rate over all of the land. This essentially means that nitrogen can be applied to cropping areas at a higher rate but must be lower over other farm areas to meet the 190kg average.

Resource consent

The use of over 190kg/ha/year of synthetic nitrogen as an ongoing activity requires resource consent. Temporary consent may also be sought until 2023 where a synthetic nitrogen reduction plan is provided which demonstrates that nitrogen will be reduced year by year to meet the N-cap by 01 July 2023.

See the Nitrogen Cap Decision Tree to help decide if you need resource consent or not.

Gaining resource consent

Resource consents for breaches of the N-cap rule have non-complying status, which provides a higher test to meet under the Resource Management Act and may not be readily obtainable.

To be granted resource consent for the ongoing discharge of synthetic nitrogen exceeding the N-cap the applicant must provide a report by a suitably qualified practitioner that sets out good practices for applying nitrogen and states that the granting of the consent will not result in and exceedance of the baseline rate of nitrogen entering water. This essentially means that the rate of nitrogen entering water based on the higher nitrogen application cannot be more than it would if a maximum of 190kg/ha/year was being applied.

The council must impose certain conditions relating to the baseline rate on any consent granted along with reporting requirements.  Any resource consent granted will have a term of no more than five years.

Nitrogen reporting

The regulations require all dairy farmers to report their nitrogen usage annually by 31 July for the previous 12-month period ending 30 June. The regulations do not prescribe how or in what form the information is to be supplied but set out the following information that must be provided:

  1. The area of land in pastoral land use in the contiguous landholding and, within that land, the areas of the following (all in hectares):
    • the land used to grow annual forage crops
    • the other land
  2. The area of land in other uses in the contiguous landholding (in hectares)
  3. The receipts for the synthetic nitrogen fertiliser purchased for the contiguous landholding
  4. The types of synthetic nitrogen fertiliser applied to the contiguous landholding and, for each type, the percentage of the nitrogen component by weight
  5. The rate at which each type of synthetic nitrogen fertiliser was applied (in kg/ha/year)—
    • to the land in pastoral land use in the contiguous landholding and, within that land, to—
      • the land used to grow annual forage crops
      • the other land
  6. To the land in other uses in the contiguous landholding
  7. The dates on which the synthetic nitrogen fertiliser was applied


From 01 July 2021 dairy farmers need to be recording the above information in a way that can be collated for the annual provision to Council.

Last updated: Aug 2023

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