The invention belongs to the field of
carya illinoensis planting, and particularly discloses a long-acting fertilization method for
carya illinoensis. The long-acting fertilization method comprises the following specific steps of S1, outwards expanding by 10 cm-20 cm by taking a
trunk of the
carya illinoensis as a center, and dividing into a circular fertilization area; S2, arranging a circle of isolation cover around the circumferential line of the circular fertilization area, inserting the isolation cover into the ground by 3 / 5 of the height, and enabling the remaining 2 / 5 part of the isolation cover to extend out of the ground; S3, arranging a circle of
fertilizer retention device of a conical structure along the outer periphery of the
trunk of the carya illinoensis in the circular fertilization area; S4, paving a humic layer with the thickness of 3 cm-5 cm on the ground below the
fertilizer retention device, and then paving a permeable
sponge layer with the thickness of 2 cm-4 cm on the humic layer; and S5, uniformly spreading slow-release
fertilizer into the fertilizer retention device, arranging an annular water spraying
pipe on the isolation cover, and enabling the slow-release fertilizer in the fertilizer retention device to permeate into the circular fertilization area by utilizing the annular water spraying
pipe. Fertilization is completed in the
irrigation process, and the effect of slowly releasing nutrients for a long time is achieved.