The paper presents tests on the pressure agglomeration process of horse manure with the addition of chopped barley straw in order to produce fertilizer granules for fertilizing small crops as part of home grown organic vegetable growing. The granulation process was carried out on a laboratory pelletizer. The experiment was carried out with the dry matter content of chopped barley straw in relation to the total dry mass of the mixture containing a straw and a horse manure, amounting to 0; 16,6; 32,7%. Middle relative humidity of the raw material was 15,2; 23,6; 30,4%. The influence of addition of a chopped barley straw and substrate relative humidity on the selected properties of the obtained granulate was determined.