Controlled release fertilizer rods and preparing method thereof

The invention discloses controlled release fertilizer rods and a preparing method thereof. The controlled release fertilizer rods are prepared from 2-6 parts of water-soluble water-retaining agents, 15-35 parts of nitrogen fertilizer, 10-25 parts of phosphate fertilizer, 10-30 parts of potassium fertilizer, 5-10 parts of medium trace element fertilizer and 10-40 parts of filler. The preparing method of the controlled release fertilizer rods comprises the following steps that the phosphate fertilizer, the nitrogen fertilizer, the potassium fertilizer and the medium trace element fertilizer are weighed according to the dosage, are smashed respectively and pass through a 20-mesh screen, the water-soluble water-retaining agents, the filler, the smashed nitrogen fertilizer, the smashed phosphate fertilizer, the smashed potassium fertilizer and the smashed medium trace element fertilizer are added into a chufa type coating machine together, a certain amount of water is sprayed through atomization pressure, and the materials are evenly mixed, added into a fertilizer forming machine and squeezed into the controlled release fertilizer rods. After the controlled release fertilizer rods are applied into soil, the fertilizer rods dissolve slowly, nutrients can be easily absorbed by crops, the nutrient supply time is prolonged, and the utilization rate of fertilizer can be effectively increased; in addition, the production process is simple, quality can be adjusted as needed, fertilizer application operation is easy and convenient, the controlled release fertilizer rods can be easily accepted by peasants and are suitable for being applied to trees with economic value and fruit trees in mountainous areas, and significant social benefits and wide application and popularization prospects are achieved.