It takes about 2 to 3 days for molds to appear on white bread, depending on humidity, exposure to sunlight and temperature. Mold or fungi grows rapidly in places that are warm, dark and moist.
All molds appear greenish to black in color. Fungi or mold grows with the help of spores. These spores are always present in the air, waiting for the right environment to grow. Fungi feeds on dead or decaying organic matter, such as plants and animals. Places experiencing a humidity of over 70 percent are likely to have rampant mold growth, as moisture is an essential factor for speeding growth.