Z Zakładu Uprawy Roślin Szklarniowych
Instytutu Sadownictwa i Kwiaciarstwa w Skierniewicach
Abstract. As an effect of many years effort the new CEN standards are introduced in order to unify the methods of determining physical and chemical properties of horticultural growing media in European scale. Methods being still commonly used in diagnostic purposes in Holland and Germany are described, as they can possibly be admitted as alternative standard methods.
Key words:
growing media, horticultural substrates, analytical methods, standardization
Summary
Methods of chemical analyses used in diagnostic purposes in Holland and Germany are described. In Holland the main method is based on the water extraction in substrate-water ratio of 1 + 1.5. It is used for determination of EC, macro- and micronutrients mainly in peat-based growing media. It is applied to all substrates containing ≥ 50% v/v of peat, cocofibers, bark or other fibrous material of natural origin. In Germany for the same purpose the method based on the extraction with the solution of calcium chloride and DTPA (CAT method) in substrate-extract ratio of 1 + 5 is used. It is applied to bulk substrates. As diagnostic method in German laboratories for P and K determination the extraction with the solution of calcium acetate and calcium lactate (CAL method) is commonly used.