CNUM1Assess nutrient management and produce a review report

What it actually is

One thing before anything else, because it changes who this page is for. This action sits in the SFI 2024 expanded offer, and the SFI 2026 offer that followed it does not include it. Defra's published reasoning was that CNUM1 has very high uptake but is being removed because it does not deliver direct environmental benefits and therefore gives very low value for money. It went out as one of five planning actions taken out in the same round, alongside the IPM plan CIPM1, the soil assessment CSAM1, the hedgerow assessment CHRW1 and the moorland record CMOR1, with the same reasoning given for each. So if you hold CNUM1 in an existing agreement, this page is for you for the rest of that agreement's term; if you are planning a new application, this is not an action you can add to it. Check your own agreement, and treat your agreement documents as the authority on what you hold.

Source: GOV.UK, SFI 2024 actions print version, page 424, checked 23/08/2026, and the Defra farming blog post of 24/02/2026, checked 24/08/2026, which is the source of the reasoning quoted and of the list of removed actions. Oakbank's report on the SFI 2026 offer, checked 23/08/2026, reports the same removal.

The action itself: a FACTS qualified adviser, one certified under the Fertiliser Advisers Certification and Training Scheme and on the BASIS Professional Register, visits the farm, assesses how you currently use nutrients, identifies where you could use them more efficiently, and helps produce a written review report. A report produced by a FACTS qualified adviser within the previous 12 months counts. The first assessment and report happen within 12 months of the action's start date, and both are reviewed in each following year of the agreement.

GOV.UK's stated aim is that you assess and plan your nutrient use more efficiently and effectively, and optimise your use of organic sources of crop nutrition.

It is an agreement-level action, one flat payment for the business rather than a rate on parcels, needing at least one land parcel below the moorland line linked to your SBI.

Source: GOV.UK, SFI 2024 actions print version, page 424, checked 23/08/2026.

What it pays, and what that comes to

The rate is in the panel at the top of this page. It is a flat payment for the agreement, not a rate per hectare, so it is the same money whatever the size of the farm:

Source: GOV.UK, SFI 2024 actions print version, page 424, checked 23/08/2026. The rate shown at the top of this page comes from Tilth's copy of the GOV.UK action catalogue and carries its own last-checked date.

Is it worth it on your ground?

As with the IPM plan, no standard fee for a FACTS adviser's visit and report is published anywhere we can point to, so the sum is your adviser's quote against the flat rate, and three things shape it.

Whether the adviser already comes. On farms where a FACTS qualified agronomist or fertiliser adviser already plans the nutrient programme, the assessment formalises work that is largely happening, and the report may be close to a write-up of the existing conversation. An existing report from the previous 12 months satisfies the first year outright, which is worth checking before anything is commissioned.

What the review leans on. The guidance describes an assessment built on soil tests for pH, phosphorus, potassium and magnesium in each field, ideally every 3 to 5 years, plus a proper accounting of what your manures, slurries, digestate and legumes already supply before a kilo of bag nitrogen is ordered. The sampling is its own cost, priced by your lab, and it is worth having whether or not this action exists; the free Tried and Tested templates and AHDB's RB209 are the tools the guidance names for the arithmetic.

The flat rate again favours the smaller farm. The visit does not get much longer as the hectares grow, and the payment does not grow at all, so the margin between fee and payment is widest where farms are smallest.

Source: GOV.UK, SFI 2024 actions print version, page 424, and How to do the SFI actions for nutrient management, checked 23/08/2026. The reasoning is Tilth's own and adds no requirement beyond what the GOV.UK action page sets out.

Does it work, and what makes it work better

This section is what we have found in published sources about the practice this action pays for. It is not scheme guidance, it is not Defra's or the RPA's view, and it adds no requirement beyond what the GOV.UK action page sets out. We have named every source and given the date we checked it. What it means for your ground is your decision.

Like the IPM plan page, this one is honest about being different. The action pays for an assessment and a document, and we have found no published study of whether holding a nutrient review report, as distinct from doing what it recommends, changes what a farm applies or loses. Conservation Evidence, whose graded assessments anchor the evidence sections across this site, assess field practices rather than paperwork, and hold no assessment of this one.

The practices the review points at are another matter. The review's whole logic, count what the soil and the muck already supply, then buy only the balance, is the arithmetic RB209 exists for, and the losses it is trying to prevent are measured territory: the evidence section of our winter cover crop page carries a British study on sandy soils in which holding nutrients over winter with a cover cut nitrate leaching by 79 per cent at one site and 42 per cent at another. A review that changes what goes on in August changes what is there to leach in November. And where the review recommends building nitrogen from legumes rather than the bag, our legume fallow page carries the evidence on how those mixes behave and collapse over time.

Source: GOV.UK, How to do the SFI actions for nutrient management, checked 23/08/2026, and the sourced evidence sections of the CSAM2 and CNUM3 pages on this site.

What we have not found. Any study testing whether farms holding a written nutrient review apply less, spend less or lose less than farms without one. As on the IPM page, that is not a claim the reviews do nothing; nobody appears to have measured it.

What follows is Tilth's own reading, and it adds no requirement beyond what the GOV.UK action page sets out.

Of the three assessment actions the 2026 offer dropped, this was the one with the most obvious route to paying for itself, because its subject is the farm's biggest variable cost. A review that trims even a modest slice off the fertiliser bill by properly crediting the muck and the legumes is worth more than the payment, and that stays true now the payment is closed to new entrants. The honest caveat is the same as on the IPM page: the value lives in the quality of the look, not the existence of the document, and a report written to bank a payment saves nobody a kilo of nitrogen.

What you actually have to do

Within 12 months of the action's start date, have a FACTS qualified adviser visit the farm, assess your current nutrient use, identify opportunities to use nutrients more efficiently, and help produce a written review report. A report produced by a FACTS qualified adviser within the previous 12 months counts for the first year. In each following year of the three year duration, reassess and review the report.

Source: GOV.UK, SFI 2024 actions print version, page 424, checked 23/08/2026.

The guidance describes the assessment, as advice rather than requirement, as calculating crop nutrient and pH requirements, testing soil in each field for pH, phosphorus, potassium and magnesium, ideally every 3 to 5 years, with sampling suggested between September and March when levels are at their lowest, calculating what organic sources already supply, legumes, manure, slurry, digestate and crop residues, and only then calculating the artificial fertiliser needed so the crop's requirement is not exceeded. It points to AHDB's Nutrient Management Guide, RB209, and the free Tried and Tested plan templates, and to the BASIS Find an Adviser tool for finding someone qualified.

Source: GOV.UK, How to do the SFI actions for nutrient management, checked 23/08/2026.

Where it can go, and what rules it out

An agreement-level action rather than a parcel one, covering your agricultural land below the moorland line, with at least one land parcel linked to your SBI. The action page lists it as compatible with all other SFI actions and all CS and ES options, except the moorland assessment actions CMOR1 and MOR1 and its own earlier version NUM1, so a farm still holding NUM1 from the 2023 offer cannot hold both.

Source: GOV.UK, SFI 2024 actions print version, page 424, checked 23/08/2026.

Things worth watching

This section is Tilth's own reading of where this action is easy to get wrong. It is not scheme guidance, it is not sourced from Defra or the RPA, and none of it adds a requirement beyond what the GOV.UK action page sets out.

Check for an existing report first. If a FACTS adviser wrote a nutrient plan for you in the last 12 months, year one may already be satisfied. Farms in an NVZ, or working to Red Tractor's nutrient planning expectations, have more of this in a drawer than they think.

FACTS, not BASIS alone. The IPM action's BASIS crop protection certificate does not cover this one; the qualification here is FACTS, on the BASIS Professional Register. Same register, different certificate, and the report needs the adviser's name and FACTS registration number kept with it.

Old soil tests hollow out the review. The assessment stands on field-by-field pH, P, K and Mg figures, and the guidance's ideal is tests no more than 3 to 5 years old. If half the farm's tests are older than that, the honest first step of this action is a sampling round, priced and booked before the adviser's visit, not after.

The report changes nothing by itself. Nothing in the action requires you to follow it. The scheme's money for practice sits elsewhere, the legume fallow in CNUM3 and the cover crops that hold nutrients over winter in CSAM2 and SOH3, and the review is a sensible place to decide whether they suit you.

Three reports, not one. The yearly review is a reassessment, and manure analyses, cropping and indices move year to year. A report that never changes across three years of moving inputs reads as a formality, because it is one.

Keeping the evidence

Also Tilth's own reading. GOV.UK sets the requirements; what follows is a practical suggestion about record keeping.

GOV.UK asks you to keep the written review report with its assessment documentation, and evidence of the adviser's FACTS qualification, their name and registration number.

Version the reports as three dated documents rather than one overwritten file, keep the adviser's details on the report itself, and file the soil analyses the review leaned on alongside it, because the report's numbers are only as good as the tests behind them and the two belong together.

Tilth stores documents against the farm with dates, and holds your soil test results in the app, so the reports and the analyses they rest on live in the same place.

The part only your own ground can answer

What the muck is worth. The review's biggest lever on farms with stock or muck for spreading hides in the organic nutrient account, what the manures, the slurry and the legumes already supply, and that number is different on every farm and every year. Tilth records your applications field by field, holds your soil tests, and runs RB209 recommendations against them, which is the same arithmetic the review starts from, kept current between the adviser's visits. Request an invite.