Abstract: A nutrient composition improved over the state of the art and which releases the nutrients contained therein in a time-controlled manner in the rhizodermal and epidermal region of the plants. The nutrient composition for plants contains at least one mixed-metallic crystalline orthophosphate of the type [Ta(M1 M2 M3 . . . Mx)b(PO4)c.nH2O], wherein T is selected from NH4, K or CH4N2O, M1, M2, M3 . . . Mx are metals selected from Mg, Ca, Mn, Fe, Co, Ni, Cu and Zn, a=0 or 1, wherein b=3 when a=0 and b=1 when a=1 and wherein c=2 when a=0 and c=1 when a=1 and wherein 0<n<9, wherein the mixed-metallic crystalline orthophosphate contains at least two different metals M1, M2, M3 . . . Mx, with the proviso that at least one of said at least two different metals is selected from Mn, Mg and Ca, wherein the total proportion of Mn, Mg and/or Ca in total is in the region of 0.5 to 90 mol-% with respect to the total amount of all metals contained in the mixed-metallic crystalline orthophosphate.