Taro leaves and lotus leaves are waterproof. Maybe they have the same reason. This is why lotus leaves are waterproof. Numerous micron-sized waxy papillae structures are attached to the surface of leaves. When observing these papillae with electron microscope, we can see that many nanoparticles with similar structures are attached to the surface of each micron-sized papillae, which scientists call the micro-nano dual structure of lotus leaf. It is these tiny double structures that make the contact area between the lotus leaf surface and water droplets or dust very limited, so there is a phenomenon that water droplets roll on the leaf surface and take away dust. Water will not stay on the surface of lotus leaves.