Using synthetic nitrogen fertilisers

You can spread up to 190 kilograms of synthetic nitrogen per hectare on any grazed land without resource consent under the Government's National Environmental Standards for Freshwater Regulations 2020 (NESF).    

In July 2021 it became illegal to spread any more than this.

Synthetic nitrogen fertiliser is any substance (either solid or liquid) that is more than 5 per cent nitrogen by weight and applied to any plant or soil as a source of nutrition.

This includes:

• any manufactured urea
• diammonium phosphate
• sulphate of ammonia.

It does not include soil treatment or fertiliser that is made from plant or animal waste that is:

• composted
• mixed
• dried
• pelleted.

Fertiliser reporting requirements

Dairy farm operators must send us annual reports showing their synthetic nitrogen fertiliser use.

This information is due every year on 31 July.

It should cover the previous financial year, from 1 July to 30 June.

Reporting tools

There are three tools farmers can choose from to submit records of synthetic nitrogen use:

• Ravensdown’s HawkEye.
• Balance’s MyBallance.
• The regional sector's web portal N-Cap.

If you are not currently a customer of Balance or Ravensdown, you can still use their tools. Contact the companies directly for further information.

If you are planning to use the regional sectors web portal N-Cap, you will need to use our Excel spreadsheet calculator to work out your synthetic nitrogen use.

See Regional sector N-Cap Youtube channel for video instructions on how to use the calculator and web portal to enter your data.

Get a copy of N-Cap synthetic fertiliser application rate calculator

You can use this tool to calculate your N-Cap application rate.

See Nitrogen Use Recording Help Centre and download the spreadsheet.

Information you need to provide

You will need to provide us with:

• the total land area of your farm in hectares
• the total land area used for grazed land split into forage crops and non-forage crops in hectares
• the total land area of ungrazed land in hectares
• kilogram of nitrogen fertiliser applied for each land use category
• name(s) of the fertiliser applied (including its nitrogen percentage) for each land use category
• records of synthetic nitrogen fertiliser purchases (such as receipts)
• your New Zealand Business Number (NZBN). See Applying for an NZBN
• your dairy supply number.

Email monitoring@aucklandcouncil.govt.nz if you have any questions about the new regulations or your nitrogen reporting.

See Resource Management (National Environmental Standards for Freshwater) Regulations 2020 for more information on the regulations and reporting requirements.

Exceeding the synthetic nitrogen cap

If you cannot meet the synthetic nitrogen cap (at both property and hectare level), you will need to apply for a resource consent.

If you already have a resource consent for your farm, you will still need to comply with rules in the NESF restricting synthetic nitrogen fertiliser use.

Fertiliser cap time extension

Previously, if you needed more time to reduce your synthetic nitrogen use, you could apply for a short duration resource consent to cover the transition period.

The time extension was only until 1 July 2023. After that date, you needed to be operating at or below the nitrogen cap.

If you need more time to reduce your synthetic nitrogen use, you can apply for an extension of up to five years.

You will need to complete a more comprehensive resource consent application for this extension.

More information

See Ministry for the Environment for synthetic nitrogen cap guidance documents covering differing types of farming operations.

You can also contact your fertiliser supplier for more advice on measuring and meeting the synthetic nitrogen cap.

Code of practice for fertiliser nutrient management (PDF 9.9MB).

Fertiliser Association of New Zealand.