Compositions of cyanamide and polyhydroxy organic compounds are provided, along with urea compositions. These compositions can be used for controlling the growth of unwanted and deleterious organisms. The polyhydroxy organic compound could be glycerin (glycerol), a sugar alcohol, ethylene glycol, propylene glycol, erythritol, xylitol, or mannitol. The composition can also include an alkanoic acid (propionic acid), a strong base (KOH), and a mineral acid (phosphoric acid).