humic acid used as fertilizer and promoter. soil ameliorator,plant-growth stimulant. PH value 3-4 Solubility: slight 65% Usage:1) Agriculture : With high content of organic matters,natural humic acid is the best additive for the organicfertilizer, raw material for humates based fertilizers and also can be used as soil ameliorator, plant growth stimulator and fertilizer improver.2) Industry: Used ...