The invention discloses a preparation method of a microbial
fertilizer. The method comprises the following steps: performing pretreatment on a
rape seed cake to obtain a first
fermentation product; performing pretreatment on straws to obtain a second
fermentation product; taking garlic, purslane, herba houttuyniae, mulberry leaves,
lotus leaves,
bitter gourd vines, pine needles,
Artemisia argyi,
Oenanthe javanica,
Toona sinensis leaves,
Allium tuberosum and konjak whole plants, performing pulverization, performing uniform mixing, adding water, performing decoction for 7-8 hours, inoculating
photosynthetic bacteria into the filter residues, and performing anaerobic
fermentation to obtain a third fermentation product; taking
potassium solubilizing
bacteria,
phosphate solubilizing
bacteria,
Bacillus subtilis and
photosynthetic bacteria, and performing mixing to obtain a mixed
microbial inoculant; and mixing the first fermentation product, second fermentation product, third fermentation product and mixed
microbial inoculant, soaking the mixture in the filtrate obtained in the step 3 for 2-3 days, spraying
sugar water, performing fermentation, stopping the fermentation when the central temperature is higher than 50 DEG C, and performing
air drying on the fermentation product, thereby obtaining the microbial
fertilizer. By using the microbial
fertilizer, the consumption of chemical fertilizers can be obviously reduced; and the microbial fertilizer is capable of loosening the soil, effectively inhibiting diseases and pests and increasing the
crop yield per unit area.