Preparation method of composite fluid fertilizer and application thereof

The invention discloses composite fluid fertilizer. The composite fluid fertilizer comprises, by weight, 20-40 parts of water, 1-6 parts of microelements, 10-30 parts of urea, 10-40 parts of pyrophosphate, 10-30 parts of organic acid sylvite and 0-2 parts of acidoid. A preparation method of the composite fluid fertilizer comprises the step of adding the microelements, the urea, the pyrophosphate, the organic acid sylvite and the acidoid into the water in sequence according to the mixing ratio. The composite fluid fertilizer has the advantages that the content is higher, and the effective content can reach above 60% and exceed that of common solid water-soluble fertilizer; the composite fluid fertilizer is dissolved rapidly and completely, no water-insoluble matter exists, and dripping nozzles are not blocked at all; the composite fluid fertilizer is easier to store and transport, and no caking or moisture absorption phenomenon occurs; by raising the nutrient content per unit weight, the packaging, storage and transportation cost is reduced.