Why re-deposition on the flower dew?

The roses with sweet aroma and the delicate petals sparkling with dewdrops can make the heart of the most icy heart crush.

But take a closer look at those dewdrops. They become round droplets rather than flowing, the main reason is that water cannot easily cling to the material that makes up the petal surface.

But water does not flow. So what are they attached to on the petals?

The dense carpet of tiny bumps surrounded by even smaller ripples made the dewdrop settle on the petals. (Photo: Dreamstime)

To find the answer, a group of chemists led by Lin Feng of Tsinghua University in Beijing scanned with a scanning electron microscope. What they observed was the thick, rugged convex carpet covered by even smaller lines. Feng's group had molded the petal plastic mold to verify if it was this structure, but not the chemical composition of the petals that kept the dewdrops. Just like real petals, plastic petals also keep the dew even when it is flipped down.

It is the surface texture that makes the magic. The texture is also important with what is known as the "lotus effect" that causes water to form round drops and then drift down to leaves and petals in many plants, enticing it with both dust and garbage. But the main difference is: for surfaces that float water, tiny bumps with wax-covered peaks are separated by narrow troughs so they are less exposed to water.

Electronic scanning micrograph reveals the structure of rose petals that make dew droplets stay fixed. (Photo: Feng et al., Tsinghua University)

Feng argued that the wax-free 'petal effect' may have helped it attract pollinators by retaining the glitter dewdrops.

Plastic petals like Feng's can be produced at low cost as well as used for many commercial purposes based on the unique properties of rose petals. But even dozens of fake flowers cannot express love messages like real roses.

The discovery was published in Langmui