Stable form of iron humate or of other meso and micro nutritive elements available for plant nutrition and method for obtaining it

Abstract

Described herein is a complex between humic substances and iron denominated "iron humate" characterized in that it has a structure of the type: ##STR1## where the metal is protected from the pyrophosphate and from the humic substances (SU), obtained through a method comprising the following phases: a) dosage of the humic extracts b) purification of said humic extracts through centrifuging or filter pressing to eliminate any suspended particles c) transfer of the floating product into a mixer d) preparation of a solution of K.sub.4 P.sub.2 O.sub.7 10H.sub.2 O e) mixing solution d) with an aqueous solution of FeSO.sub.4 7H.sub.2 O containing a minimum quantity of H.sub.2 SO.sub.4 operating slowly and keeping the humic extract under vigorous agitation f) after agitation for a few minutes, rapid drying at 60-90.degree. C.

Dependencies are inferred from the claim text.