A forest fire retardant composition contains water and a retardant compound that includes a halide salt, a non-halide salt, a metal oxide, a metal hydroxide, or combinations thereof. The halide salt may be magnesium chloride, calcium chloride, or both. The magnesium chloride hydrate has a formula MgCl2(H2O)x, wherein x is at least one of x=1, 2, 4, 6, 8, or 12. The calcium chloride hydrate has a formula CaCl2(H2O)x, wherein x is at least one of 1, 2, 4, or 6. The composition may be in the form of a liquid concentrate or a final diluted product. The final diluted product is effective in suppressing, retarding, and controlling forest fires while exhibiting corrosion resistance and low toxicity.