Water lilies, Lotus, and surface wetting

Last weekend I visited Hughes Water Gardens located near Wilsonville, OR

This nursery specializes in water plants and it was very interesting to see the large number of plants they had. However, I had the most fun looking at the leaves from the water lilies and the lotus plant. Their surface exhibit superhydrophobic characteristics. This means that when water comes into contact with the leaf surface, it beads up and rolls off the leaf.

When water rolls off, it cleans the surface of the leaf. This is why these leaves always seem to remain clean in murky ponds. This behavior is known as the Lotus Effect.

The Lotus Effect is attributed to both micro-scale surface bumps and nano-scale hair like structures present on the leaf surface. These surface structures trap air underneath the water droplets and create the superhydrophobic characteristics.  

 

Source: [1]

Reference:

[1] Cheng, Y., Rodak, D., 2005, “Is the lotus leaf superhydrophobic?”, Applied Physics Letters, 86, 144101