What does a notified body need to assess my biostimulant trials?

The main question is simple: does the evidence support the claim?

The assessor needs to understand what was tested, how the work was done and what the results mean. It also considers whether the evidence fits the product and the way customers will use it.

A promising trial is not the same as an accepted dossier. Trial evidence is only one part of the product assessment.

This is an editorial overview of common evidence questions, not an official acceptance checklist. Your notified body determines what is needed for your assessment.

Be clear about the effect you want to claim. “Makes plants stronger” is too broad to explain what you tested.

For example, you may want to show better use of nutrients or better tolerance to drought. The trial must help answer that specific question. The claim on your label should not promise more than the evidence supports.

The assessor needs confidence in the work, not just an attractive graph. The trial should use a fair comparison and suitable methods. The people doing it should have the knowledge and experience needed.

The company carrying out the trials must be able to show that it follows the quality criteria for the approach used. Under EN 17700, this means competent staff and properly managed trial work. Certification is not a blanket requirement for every biostimulant efficacy trial.

Ask your notified body whether it requires a particular certification, accreditation or recognised quality scheme for the work you plan to submit. Check this before choosing a trial provider. A certificate alone does not guarantee that the trial evidence will be accepted.

Keep the records behind the results. Explain problems or changes openly. This makes it easier to understand how you reached the conclusion.

The assessor should be able to link the tested product to the product in your dossier. Identify the version or batch used, and explain differences in composition or intended use.

Then connect the trial question, method, measurements and conclusion. A report should explain why the result supports the proposed claim, including where that conclusion stops.

A useful report gives more than a favourable percentage. It explains the comparison, variation between observations and the analysis used.

Include results that did not show a benefit, as well as positive results, and explain important problems. A programme with mixed results needs an honest interpretation, not just a selection of the best graphs.

If your evidence follows EN 17700, the assessor needs to see how the programme meets the chosen route, not just a total count. For a one-crop claim, the individual-trial minimum is 3 trials; the alternative is at least 1 trial series, containing at least 4 trials or 15 strip trials. Those alternatives have different analysis conditions.

For replicated field work, check that the provider explains the minimum of 4 replicates per treatment. In EN 17700-1:2024, the significance thresholds are p < 0.15 for field/protected-crop trials and field series, and p < 0.10 for individual controlled-condition trials. The underlying data and analysis must let the assessor check the conclusion.

These are selected standard facts, not a universal NoBo acceptance checklist. A three-trial report can still leave gaps if it concerns the wrong formulation, unsuitable growing conditions or a claim broader than the evidence. Include inconclusive results and explain the whole programme rather than submitting only the most favourable trials.

Ask how it plans and reviews the work, trains the people involved, checks its measurements and keeps the records. These are practical ways to understand how the work is managed, not a reproduction of a standard’s qualification checklist.

If the provider has a certificate or accreditation, check what work it actually covers. Laboratory analysis and field efficacy trials are different activities. A certificate for one does not automatically cover the other.

The notified body can clarify which quality evidence or recognised scheme is relevant for your assessment.

You want to claim drought tolerance, but the report contains only higher yield from a season described as dry. The assessor may still need evidence that the crop experienced relevant stress and that the comparison can explain the claimed benefit.

The issue is not that yield is useless. It is that the result needs enough context to answer the claim. Discuss the gap before deciding whether further trials or better supporting records are needed.

Discuss your intended claim and proposed approach with your chosen notified body before committing to trials. Ask what evidence it will need and whether your plan is suitable for the assessment.

If you already have trial results, ask how they can be used. Do not assume they will be accepted, or that you must start again.

Early discussion can help avoid missing evidence and unnecessary work. It is not a guarantee that the final results will be accepted.

The EN 17700 series provides a recognised framework for evidence supporting plant biostimulant claims. Using standards is voluntary; the product must still meet the legal requirements.

This article combines original explanations with selected numerical and scope requirements from the standards. It is not a complete protocol or a substitute for the official standards and their full conditions. Agree the chosen approach with a qualified trial specialist and your notified body.

• The claim promises more than the trials show.
• It is not clear whether the tested product matches the product being assessed.
• The comparison does not clearly show the product’s effect.
• The report gives a result, but the records behind it are missing.
• Changes or problems during the work are not explained.
• The evidence does not cover the intended crops or uses.

These gaps may lead to questions or further work. Discuss them with your notified body rather than assuming that a positive result will be enough.

RecyFert helps organise the trial evidence in your product dossier and identify information that is missing. The trial provider is responsible for its work. The manufacturer stays responsible for the product. The notified body makes the assessment decision.