Crushed limestone (particle size below 3.2 mm) was mixed either with an aq. soln. of Na lignosulfonate (concn. 5-15% by mass) or with aq. H2SO4 (concn. 10%) in a lab. granulator. The wet granules (size 4.29-4.57 mm) showed the crushing strength 5.20-9,8 N/granule. Under pilot plant conditions, gypsum was also added (1-5%) to the fertilizer and the granules were dried down to the moisture content 1.5-3.0% by mass. The granules were 2-5 mm in size and showed an increased crushing strength (higher than 20 N/granule).