Alum (tawas) can be used to reduce the incidence of bacterial soft rot in cabbage. It penetrates host tissues and prevents the development of the disease even if bacteria have already set in. The commodity is first trimmed to eliminate injured or infected parts. Alum dissolved in warm water is then applied to the cut butt end by brushing, wiping, or spraying. One kilogram of alum is enough to treat 2 tons of cabbage.