PRF1: Variable rate application of nutrients

The following changes have been made to this action for SFI26 (compared with the SFI24 version):

• there’s a new exception for an initial ‘wake up’ application of nitrogen at a ‘flat rate’
• minor updates to standard wording which appears in all area-based SFI actions

This action’s aim is that precision farming equipment is used to apply all major nutrients:

• at a variable rate, which means the nutrient application rate is automatically varied
• to match the nutrient needs of crops on different areas of land

The purpose of this is to:

• reduce over-application of nutrients
• improve yields from more consistent crop growth and quality
• improve water and air quality

What you must do

You must apply all major nutrients across the land entered into this action using Variable Rate Application (VRA) equipment.

The VRA equipment must be either:

• pre-programmed with a ‘variable rate file’ using data from zonal soil or crop testing and analysis or remote sensing
• linked to a tractor or sprayer mounted crop reflectance sensor

You must make sure the VRA equipment automatically varies the application rate of the major nutrients in a way that can reasonably be expected to achieve this action’s aim.

The only exception to this is if you apply an initial ‘wake up’ application of nitrogen  to arable crops in late winter or early spring. In this case, you can:

• use equipment that is not VRA equipment
• apply the nitrogen at a ‘flat rate’ for the initial ‘wake up’ application only

For the purposes of this action, major nutrients include nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg), as relevant, contained in:

• manufactured fertilisers – solid or liquid
• solid manures – such as farmyard manure, poultry litter, sewage sludge or biosolids
• slurry or digestate, including separated liquid

You do not need to use VRA equipment to apply:

• micro-nutrients, such as boron or sulphur
• lime, because is not a nutrient – it helps to increase the availability of major nutrients and controls soil acidity (pH)

‘Zonal’ soil testing means you divide land parcels into soil management zones and take soil samples within each zone.

The data from zonal soil testing and analysis must cover a minimum of P, K, Mg and pH. You can use existing zonal soil testing analysis if it:

• meets this action’s requirements
• is less than 5 years old

When to do it

You must do this action from its start date, throughout each year of its 3-year duration.

Evidence to keep

You must keep evidence to show what you’ve done to complete this action, such as:

• invoices for zonal soil testing and analysis
• the ‘variable rate file’ uploaded to the VRA equipment
• an ‘as applied’ VRA record at a land parcel level
• initial flat rate N application records showing the product, the rate and date of application (if relevant)
• field operations at a land parcel level and associated invoices
• contractor’s invoice if you use a contractor to do this action

If it’s not clear that you’ve done this action in a way that could reasonably be expected to achieve its aim, we may ask for this evidence. You must supply the evidence if we ask for it.