How does sugar preserve a flower?

It all boils down to water. Sugar is what’s known as a hygroscopic substance, which means it draws water molecules from the surrounding environment by absorption. Microbes like bacteria and fungi need water to metabolize, grow and reproduce, and sugar denies them that. Thus, even though a few microbes might be present on a candied flower, they’re essentially immobilized. The applications of sugar is a method of dealing with micro-bugs that’s every bit as effective as applying salt, though not technically as lethal, since salt essentially implodes microbes, removing their water by osmotic pressure. Call it cruelty-free preservation, for those concerned with microbe rights.