Have you ever heard of a frost flower? Ever see one?
In Kentucky, frost flowers can be found among tall weeds and plants located near a field or prairie. Likely candidates for frost flowers include wingstem, ironweed, goldenrod, ragweed and other herbaceous plants boasting a thick, hollow stem.
“They can be found pretty easily throughout the state, especially during a heavy frost or freeze in spring and fall when air is cold and the plants have a high moisture content,” says Jeff Sole, the Conservancy’s Director of Conservation Programs.
Certain conditions need to be just right for the formation of frost flowers:
- freezing air temperature
- soil that is moist or wet but not frozen
- a plant’s stem that has not been previously frozen
Understanding how a frost flower forms requires conjuring up some middle school science. Through a process called capillary action, water is drawn upward from the ground and into a plant’s stem. As the water freezes, it expands and creates microscopic cracks. Then, when the water vapor exits those cracks, it freezes, emerging as paper thin “petals” of ice.
Because water is continually being drawn up into a plant’s stem, the process of cracking and freezing can result in many petals. The size of the cracks determines the shape of the petals, resulting in unique flowers of all shapes and sizes!
Similar to snowflakes, no two frost flowers are alike.
According to the Conservancy’s volunteer Preserve Steward, Ken Brooks, you can find frost flowers at many of the Conservancy’s nature preserves. “You can find them along the fields located at the Brown/Crutcher/Wallace Nature Preserve,” says Brooks. “Another good spot is along the main trail at Dupree—between the parking lot and where the trail enters the trees.”
The best time to search for frost flowers is early in the morning, before the sun rises, on a day with freezing air temperatures and unfrozen ground. But remember, you can’t pick the flowers as your warm hands will melt these masterpieces of nature. Maybe bring a camera instead.
Start the search! Late winter and early spring provide the perfect opportunity to visit one of our nature preserves in search of frost flowers. If you do, please share them with us on Facebook or in an email to firstname.lastname@example.org.