How hot must you get to kill mold?

Hot, as mold mainly grows because of dampness. When it is cold, the air often will be dry and there is less amounts of humidity it in. With less humidity, there is less moisture for things to grow mold on them. Think about a loaf of bread. If you freeze a loaf of bread, it won't mold for a very long time. If you leave it out on your countertop for over two weeks mold spores begin to grow on it. Heat also is a source for things to grow. Most flowers, trees, grass, etc don't grow in the cold. Mold is not any different.