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Now is a good time to look for the pattern of ice flowers on the asphalt in the mornings. In the photo above the ice flowers have been photographed on a window: the asphalt flowers are much darker, as their background. Usually we notice the ice blooms on windows when it is cold outside. The climate in houses in midwinter is just right for their growth: room warmth on one side and very cold weather on the other. At the window these meet in the right proportions. But now, early spring, is the time of ice patterns on the ground.

 

You will find ice flowers outdoors when the weather happens to be right – above-zero in daytime and frost at night.

 

How does this flower grow? To start with the asphalt must be damp enough and with a little water but not too much. At night it freezes. If an ice crystal finds enough smooth surface, it begins to produce similar patterns around itself. It grows and grows, one crystal layer after another. To grow even crystals need food – nicely humid air. It swallows and freezes it, making a pattern. The whole pattern is as the original but at the same time never recurs.

 

The ice flowers creep in every direction along cracks in the asphalt – until the day’s warmth destroys them again. One morning this beauty is just before our shoetips.