Long-acting fertilizer for greening seedlings and preparation method thereof

The invention relates to a long-acting fertilizer for greening seedlings, preparation and application. Raw materials are different types of controlled-release fertilizers: sulphur plus high-molecularpolymer coated urea, 8% thermoplastic and thermosetting double-coated urea, 10% recycled thermoplastic resin coated urea, urea undercoating 5% modified epoxy resin coated diammonium phosphate, urea undercoating 5% modified epoxy resin coated potassium nitrate and diammonium phosphate. A variety of coated fertilizer raw materials are utilized for compounding, the long-acting fertilizer for the greening seedlings is prepared according to the law of release of nutrients in the soil, the long-acting fertilizer can be applied into a planting hole in one time during transplanting, the root system isnot damaged, the effective period can be 2-3 years, the fertilizer utilization rate is high, and labor is saved. 本发明涉及种绿化苗木用长效肥及制备与应用。原料选用不同类型的控释肥：硫加高分子聚合物包膜尿素，8％热塑与热固双层包膜尿素，10％回收热塑性树脂包膜尿素，尿素底涂层5％改性环氧树脂包膜磷酸二铵，尿素底涂层5％改性环氧树脂包膜硝