Missouri Department of Conservation Notes Icy Frost Flowers Appearing on Cold Mornings

Kansas City, MO (STL.News) Sharp drops in overnight temperatures is prompting icy frost flowers to appear on cold mornings in the Kansas City area.  Frost flowers are ribbons of ice that form on the bases of specific wildflower stems in late autumn or early winter.  When temperatures plunged in the early morning hours of Nov. 8, frost flowers appeared at the Missouri Department of Conservation’s (MDC) outdoor garden at the Anita B. Gorman Discovery Center, 4750 Troost Ave.

A large stand of white crownbeard wildflowers in the Discovery Center’s native prairie plant area gave rise to numerous frost flowers. Crownbeard, dittany, and stinkweed are the region’s plants that most commonly host frost flowers.  For some reason, these specific species are hosts to the ribbons of ice that form when cold conditions arrive suddenly.  Most of the plants are dead or dormant in the upper growth areas.  But the lower part of the stem is still somewhat green and uploading moisture from the roots, perhaps due to the soil remaining warm for a time.  The stems split at the base as sap begins expanding while freezing.  As the sap is forced out and encounters cold air, icy ribbons of ice form in various shapes such as curls and mounds.

People who hike or hunt in November often encounter frost flowers in weedy fields and fence lines. Gardeners who include crownbeard in native wildflower landscaping get frost flowers as a final bloom of the growing season.  The plant grows tall in good soil and sun, so crownbeard is best planted at the rear of a wildflower landscape arrangement.

One caveat, frost flowers are often short lived.  They usually appear overnight and the day’s warming sun quickly melts them, unless cold persists in shady areas.  They are most common in late autumn.  But in some years, if conditions are favorable, they may occur into early winter.