A plant growing material containing a group of chemical species having a mass number of 1,000-10,000 per electric charge. This plant growing material has a function of decreasing the ionic valence of iron ions of cytochrome c by one-electron reduction from three to two and significantly promotes growth of plants. A method of producing the plant growing material including the step of performing water electrolysis using a carbon electrode. Performing electrolysis of water using a carbon electrode produces a material promoting growth of plants (plant growing material) as well as carbon dioxide at an anode. A method of growing plants using the plant growing material including the step of spraying onto leaves or supplies water containing the plant growing material to culture the plants. The method promotes the growth of plants significantly.
