FprEN 17779

• Abstract:

  This document specifies the procedure for the extraction of different organic and organo-mineral fertilizers with a solution of neutral ammonium citrate to enable a subsequent determination of phosphorus.; This document is applicable to the fertilizing products blends where a blend is a mix of at least two of the following components: fertilizers, liming materials, soil Improvers, growing media, inhibitors, plant biostimulants, and where the following category: organic fertilizers, organo-mineral fertilizers is the highest % in the blend by mass or volume, or in the case of liquid form by dry mass. If the organic fertilizer or the organo-mineral fertilizer is not the highest % in the blend, the European Standard for the highest % of the blend applies. In case a fertilizing product blend is composed of components in equal quantity, the user decides which standard to apply. Variations in analytical methods for fertilizing product blends can lead to differing results as some components or matrix interactions can affect the outcome. Validation procedures have shown that developed standard methods are robust and reliable across diverse product compositions, but possible interferences and unexpected results when analysing fertilizing product blends are possible.

• Status: Not Published
• Publication Date: 17-Feb-2027
• ICS: 65.080 - Fertilizers
• Technical Committee: CEN/TC 260 - Fertilizers and liming materials
• Drafting Committee: CEN/TC 260/WG 8 - Organic and organo-mineral fertilizers
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Start Date: 27-Aug-2026
• Due Date: 14-Mar-2027
• Completion Date: 27-Aug-2026
• Directive: Harmonized Standard2019/1009 - Regulation (EU) 2019/1009 of the European Parliament and of the Council of 5 June 2019 laying down rules on the making available on the market of EU fertilising products and amending Regulations (EC) No 1069/2009 and (EC) No 1107/2009 and repealing Regulation (EC) No 2003/2003 (Text with EEA relevance)
• Mandate: M/564 - Fertilising products in support of Regulation (EU) 2019/1009
• Mandate: M/564 Amd 1 - amending Implementing Decision C(2020) 612 as regards certain harmonised standards and standardisation deliverables, deadlines for their adoption and the duration of the validity of the standardisation request
• Mandate: M/564 Amd 2 - Commission Implementing decision amending Implementing Decision C(2020)612 as regards harmonised standards, the deadlines for the adoption of those standards and the duration of the validity of the standardisation request to the European Committee for Standardisation as regards the EU fertilising products in support of Regulation (EU) 2019/1009 of the European Parliament and of the Council
• Ref Project: oSIST prEN 17779:2026 - Organo-mineral fertilizers - Extraction of phosphorus soluble in a neutral ammonium citrate solution

• Revises: CEN/TS 17779:2022 - Organo-mineral fertilizers - Extraction of phosphorus, which is soluble in neutral ammonium citrate
• Effective Date: 11-Jun-2025

Overview

FprEN 17779: Organo-mineral fertilizers - Extraction of phosphorus soluble in a neutral ammonium citrate solution is a European standard developed by CEN/TC 260 that specifies the laboratory procedure for extracting phosphorus from organic and organo-mineral fertilizers using a neutral ammonium citrate solution. This method is crucial for the accurate determination of phosphorus content, supporting both regulatory compliance and product quality assurance in the European fertilizers industry.

The standard is applicable to various fertilizer blends, particularly when organic or organo-mineral fertilizers are the primary component by mass or volume. Where these are not the predominant component, other relevant European standards apply. The document also addresses scenarios involving blends with components in equal measures, allowing for user discretion in applying the most suitable standard.

Key Topics

• Phosphorus Extraction: Details a uniform method for extracting phosphorus that is soluble in a neutral ammonium citrate solution, ensuring consistency in analytical results.
• Applicability to Blends: Clarifies the application of the standard to blends containing fertilizers, liming materials, soil improvers, growing media, inhibitors, and plant biostimulants, focusing on cases where organo-mineral or organic fertilizers are the dominant fraction.
• Laboratory Practice: Emphasizes requirements for standard laboratory equipment, sample preparation, reagent quality, and strict adherence to safety and procedural protocols.
• Validation and Reliability: Notes that the methodology has been validated for robustness and reliability across various product compositions, while highlighting the potential for interferences due to the complexity of blended products.
• Reporting Requirements: Outlines the minimal elements required in the test report, such as sample identification, methods referenced, extraction dates, and details of anomalies during analysis.

Applications

• Quality Control in Fertilizer Production: Ensures that manufacturers and blending facilities can accurately measure phosphorus content, supporting product labeling, quality assurance, and regulatory compliance.
• Market Certification: Facilitates conformity assessments for EU market access according to Regulation (EU) 2019/1009, helping organizations demonstrate adherence to harmonized standards.
• Research and Development: Assists laboratories and researchers in developing and comparing new fertilizer formulations by providing a standardized method for phosphorus extraction.
• Product Blends Assessment: Offers a decision framework for laboratories in selecting the appropriate standard when dealing with complex fertilizer blends, minimizing result variability arising from matrix effects.

Related Standards

• prEN 17774: Specifies methods for the determination of element content in organic and organo-mineral fertilizers after extraction, referenced for analyzing the citrate-soluble phosphorus extract.
• EN 12944-1 & EN 12944-2: Provide definitional clarity for terms and vocabulary relating to fertilizers and liming materials.
• EN 1482-1, EN 1482-2, EN 1482-3: Govern sampling and sample preparation procedures, ensuring representativeness and consistency of materials tested.
• Regulation (EU) 2019/1009: Establishes the legal framework for placing fertilizer products on the EU market, under which compliance with FprEN 17779 is recognized.

By implementing FprEN 17779, stakeholders in the fertilizer sector can ensure reliable, comparable phosphorus determinations, meeting both legal requirements and industry best practices for organic and organo-mineral fertilizer products and blends.

SLOVENSKI STANDARD
01-marec-2026
Organsko-mineralna gnojila - Ekstrakcija fosforja, topnega v nevtralni raztopini
amonijevega citrata
Organo-mineral fertilizers - Extraction of phosphorus soluble in a neutral ammonium
citrate solution
Organisch-mineralische Düngemittel - Extraktion von Phosphor, der in neutralem
Ammoniumcitrat löslich ist
Engrais organo-minéraux - Extraction du phosphore soluble dans une solution de citrate
d’ammonium neutre
Ta slovenski standard je istoveten z: prEN 17779
ICS:
65.080 Gnojila Fertilizers
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 17779
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2026
ICS 65.080 Will supersede CEN/TS 17779:2022
English Version
Organo-mineral fertilizers - Extraction of phosphorus
soluble in a neutral ammonium citrate solution
Engrais organo-minéraux - Extraction du phosphore Organisch-mineralische Düngemittel - Extraktion von
soluble dans une solution de citrate d'ammonium Phosphor, der in neutralem Ammoniumcitrat löslich ist
neutre
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 260.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17779:2026 E
worldwide for CEN national Members.

prEN 17779:2026 (E)
Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Principle . 5
5 Sampling and sample preparation . 6
6 Reagents . 6
7 Apparatus . 6
8 Procedure. 7
8.1 Test portion . 7
8.2 Extraction . 7
9 Test report . 7
Bibliography . 8

prEN 17779:2026 (E)
European foreword
This document (prEN 17779:2026) has been prepared by Technical Committee CEN/TC 260 “Fertilizers
and liming materials”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede CEN/TS 17779:2022.
Compared to the previous edition, prEN 17779:2026 includes the following significant technical changes:
— the CEN Technical Specification has been adopted as a European Standard;
— title adapted;
— Introduction added;
— Scope (Clause 1) updated including the clarification on fertilizing product blends and the analytical
method to be used;
— Reagents (Clause 6) added;
— Clause 9 (Test report) added;
— Bibliography updated.
This document has been prepared under a Standardization Request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
prEN 17779:2026 (E)
Introduction
WARNING — Persons using this document should be familiar with usual laboratory practice. This
document does not purport to address all of the safety issues, if any, associated with its use. It is the
responsibility of the user to establish appropriate health and safety practices and to ensure compliance
with any national regulatory conditions.
IMPORTANT — It is absolutely essential that tests conducted according to this document are carried out
by suitably trained staff.
prEN 17779:2026 (E)
1 Scope
This document specifies the procedure for the extraction of different organic and organo-mineral
fertilizers with a solution of neutral ammonium citrate to enable a subsequent determination o
...