PROPERTIES OF GRANULAR ORGANO-MINERAL FERTILIZER AND THE INFLUENCE OF ITS APPLICATION ON SOME CHEMICAL PROPERTIES OF THE SOIL IN AN APPLE PLANTATION, JONATHAN VARIETY

The physical-mechanical properties, as pH and compressive strenght, determined for the fertilizer granules obtained by enriching the compost from urban sludge with mineral fertilizers with N, P, K, fall within the norms imposed on organo-mineral fertilizers. Applying organo-mineral fertilizer to acidic soil in an apple orchard improved the physicochemical properties of the soil. The experimental factor was the fertilizer dose, placed randomly, in five variants and four repetitions. One year after fertilization, the soil reaction was significantly improved (from pH = 5.4 to pH = 5.80). The mobile phosphorus content in the soil increased significantly in the fertilized variant with 40 t fertilizer / ha. The humified organic matter was at a high level in variant with 60 t/ha (humus = 4,25%) compared to the control variant (humus = 1.58%).