This document specifies methods for the reduction and preparation of samples of non-microbial plant biostimulants including those intended for determination of microbial pathogens and sets out the requirements for sample preparation reports. It specifies methods for the preparation of test samples and test portions from laboratory samples of plant biostimulants for subsequent chemical, biological or physical analysis. It is also applicable to the sample preparation of blends of fertilizing products where plant biostimulants are main part of the blend. Otherwise, deliverables of sample preparation relevant for the main part of the blend apply. This document does not include methods for the reduction and preparation of samples of microbial plant biostimulants, which will be covered by a different Technical Specification. NOTE This document is applicable to the category of EU fertilizing product (plant biostimulants) in the meaning of the Regulation (EU) 2019/1009.