Good Nutrient Management: Nitrogen, Phosphorous, and Supplementary Feed

How you can do this:

• To determine the level of phosphorus fertiliser needed, conduct regular soil testing (Olsen P or an equivalent, recognised soil test) for each Land Management Unit to identify trends, patterns and the impacts of nutrient management decisions.
• Tailor fertiliser applications for these different Land Management Units - annually for capital applications and biennially for maintenance applications.
• Leave an unfertilised strip as a buffer zone beside waterways, drains, and stormwater flood zones. As slopes become steeper, allow more distance.

Your own industry will have its own relevant practices and support material.

You can show you meet this GMP with: 

• Olsen-P (or equivalent) soil test monitoring results.  
• A Nutrient budget and fertiliser recommendations prepared by a certified Nutrient Management Advisor.   
• Fertiliser invoices.  

How you can do this:

Soil tests - for each Land Management Unit: 

• Soil test at least six (6) weeks before all fertiliser applications.
• Before any capital fertiliser applications.
• Biennially for all maintenance applications.
• Regularly test soil, including soil mineral N-testing to identify nutrient needs, particularly for paddocks going into crop, to identify nutrient levels. 

FertilISER APPLICATION RECORDS:

• Record all fertiliser applications – product, rate, date, location.

Nutrient budgets – prepared annually by a certified Nutrient Management Advisor:  

• Use a predictive nutrient budget (such as OverseerFM®) to manage nutrients on all land that supports your farm. Account for all sources of nutrients:
  • Soil nutrient states (including soil pH). 
  • Organic fertilisers – including liquid effluent and manure.
  • Imported feed.
  • Previous land use (grazing and crops).  

 → A nutrient budget sets the farm's annual fertiliser applications for each Land Management Unit and informs decision-making.  It needs to be updated annually or at least when the farm system changes. 
 

The Code of Practice provides practical science-based information about fertiliser use for a range of New Zealand farm systems.

Fertiliser application:

• Avoid the winter months
  • The soil temperature is assessed prior to applying N-fertiliser to ensure the crop/pasture is actively growing – minimum soil temperature at 6 °C and increasing.
  • Soil moisture levels are assessed to determine whether the soil is not saturated or is forecast to become saturated.
• Avoid applying fertiliser close to waterways, including ephemeral waters and Critical Source Areas, when heavy rainfall is forecast and run-off is likely.
• Follow expert guidelines (like using crop calculators), expert agronomic advice or codes of practice where appropriate.
• The Fertiliser Association of New Zealand's Code of Practice for Nutrient Management also provides practical science-based information about fertiliser use for a range of New Zealand farm systems.

Dairy:

• Ensure your farm's audited nitrogen management system contains recording and reporting requirements for N fertiliser (including milking platform and any contiguous support land).
• Assess pasture/crop growth against feed requirements before applying N.
• Apply N – ‘little and often' and when the pasture is actively growing.  

You can show you meet this GMP with: 

 Nutrient budget prepared by a certified Nutrient Management Advisor  

• Soil test monitoring results.  
• Fertiliser proof of placement records – product, rate, date, location.
• Pasture walk data /Feed wedge.  
• A predictive Nutrient Budget and Plan.
• N-cap records.

N-Cap records refer to the National Regulations limiting the use of synthetic N fertilisers on grazed land. Farmers must report their usage annually, ensuring it doesn't exceed 190 kgN/ha/yr. To find out more about your obligations and get guidance on what you need to do, visit our Synthetic Nitrogen Fertiliser page

How you can do this:

• Follow the Fertiliser Association of New Zealand Code of Practice for Fertiliser Nutrient Management   for handling, storage, and use.
• Locate storage sites at least 50m away from permanent or intermittent waterways, ephemeral flow paths, critical source areas, and areas prone to flooding and run-off.
• Ensure stored fertiliser is fully contained with an impervious floor, bunded, and protected from rain.
• Collect and divert any rain or water away from the storage area.

You can show you meet this GMP with: 

• Farm Map with fertiliser storage site(s) identified.  
• Fertiliser storage and handling policy.  
• Photographs and field observations of fertiliser storage areas.  

How you can do this:

• Ensure any contractors used for spreading fertiliser are accredited. The current industry standard is Spreadmark. You can learn more about the Spreadmark quality assurance programme from the  Fertiliser Quality Council. website. 
• Calibrate your spreading equipment according to its design specifications, ensuring it is tailored to the product being spread. Be sure to check both the spreading width and volume.
• Fertiliser spreading equipment is maintained following the manufacturer's instructions.
• Check for ‘paddock stripes’ after spreading.  

You can show you meet this GMP with:   

• Calibration and maintenance records.
• Contractor invoices.   
   

How you can do this:

• Store and feed that has the potential to create leachate in hard-sealed areas, collect the leachate produced, and add this to an existing effluent management system or ensure storage sumps are big enough for leachate collection of about 3m³/100T silage.
• Site and divert overland flow and rainwater away from feed storage areas.
• Site feed storage and feed-out areas must be away (DairyNZ advises their farmers at least 50m) from all waterways, ephemeral flow paths, and critical source areas. 
• Ensure silage is properly wilted before stacking (slightly damp when squeezed) to minimise leachate generation and remains sealed while stored to prevent rotting. Read more here. Consider the forecasted weather and, if using contractors for silage storage, coordinate with them early to plan the work.
• Ensure permanent feed-out areas/facilities are sealed and effluent is collected.
• Distribute feed to minimise soil damage (from farm equipment and animals) and potential surface run-off to waterways, i.e., avoid Critical Source Areas. 

You can show you meet this GMP with: 

• Farm map identifying feed storage and feed out areas.
• Feed out area design plans.
• Photographs and field observations of feed storage areas.