The invention relates to the technical field of agricultural planting fertilization, in particular to a fertilization device for agricultural mechanical planting and a using method thereof. The fertilization device comprises a support, a
traction frame fixedly arranged on the right wall of the support, a
plough assembly arranged on the lower side of the right end of the support, a crushing
assembly arranged at the lower end of the middle of the support, a subpackaging box fixedly arranged at the left end of the support, and a stirring
barrel fixedly arranged at the upper end of the subpackaging box; a rake
assembly is fixedly arranged on the
left wall of the subpackaging box; a feeding hopper is fixedly arranged at the front end of the top surface of the stirring
barrel. According to the invention, the motor rotates to drive a crushing roller to crush agglomerated and large-particle
fertilizer, the
fertilizer is mixed and stirred by a spiral stirring blade, the
fertilizer falls into the subpackaging box and then is conveyed into a discharging groove by the discharging
pipe, and at the moment, the discharging groove enables the fertilizer to fall into ploughed gully land, so that deep ploughing and fertilization are completed. The seed integrity is protected, the
survival rate of the seeds is improved, crops can conveniently and directly absorb fertilizer from root systems through deep ploughing and fertilization, favorable conditions are provided for
crop growth, and the fertilization use effect of agricultural planting is remarkably improved.