Investigations concerned the effect of raising the dose of new Z-ion zeolite substrate on cocksfoot (Dactylis glomerata L.) growth. During the pot experiment, plants were grown on degraded soil, arable soil and mixtures of degraded soil with increasing Z-ion substrate additions (1%, 2%, 5%, 10 % v/v). When the experiment was terminated, the mean values of the vegetative parameters of test species were calculated. The carbon to nitrogen ratio for cocksfoot stem biomass was determined. The enzyme diversity of the degraded soil enriched with substrate additions after cocksfoot growth (Shannon’s diversity index) was also evaluated. The application of Z-ion additions positively influenced the cocksfoot growth – the additions in the range of 1-10% v/v to degraded soil significantly increased wet and dry stem biomass, dry root biomass and total dry biomass of plants. It turned out that the Z-ion substrate addition not exceeding 1% v/v can be considered as one which – after introducing into a specific degraded soil – would give similar biomass yield of cocksfoot to that obtained on the selected arable soil. At 1% substrate dose, the carbon/nitrogen ratio in the plant material (27.17) was within the range of values ensuring the proper methane fermentation course. The preliminary studies have shown that a significant increase in enzyme diversity can be observed when there is a certain degree of root development caused by a sufficiently high addition of Z-ion substrate to the degraded soil – under experimental conditions it was 5% v/v Z-ion dose.