Afforestation method for sandy coast difficult site

The invention discloses an afforestation method for a sandy coast difficult site. The afforestation method comprises the following five steps. According to the method, the sandy soil is subjected to soil turning and rectification, meanwhile, a mixture of gravel blocks and soil is laid on the sandy soil, a water retention layer is arranged on the gravel layer, a vegetation water retention layer is formed by mixing a water retention agent and soil, before planting, soil preparation is conducted on the selected afforestation land in a depth horizontal ditch soil preparation mode, field planting marks are arranged on horizontal ditches, and then planting is conducted on the afforestation land; a soil conditioner is laid on the upper portion of the vegetation water retention layer, meanwhile, dead leaves, straw, sawdust and other natural fertilizers prone to corrosion are laid on the surface of the vegetation water retention layer, a soil sample of the soil is cultured, meanwhile, wet bryophytes are laid around a