Humans have a love-hate relationship with winter. On one hand it’s cold and sometimes dreary and on the other it is a respite from the heat and bugs of summer. With unsurpassed vistas, clear woodland paths and limitless opportunities to spot birds, raptors and other wildlife, winter also allows for some of the best hiking of the year. During winter hikes one can spot some of nature’s best architectural wonders, specifically those created during freezing weather, such as ice falls, hoary frost and frozen fog. My all-time favorite wintertime sculpture has to be the elusive and transient frost flower.
Of course the frost flower is not a true flower at all, but rather, a sculptural one made up of one or more delicate ribbons of ice. While the term frost flower is most commonly used to describe the stunningly delicate and ephemeral sculptures, they are also known as ice flowers, ribbon ice, ice blossoms, ice needles, ice castles, rabbit ice and ice fringes. Whatever you prefer to call them, frost flowers are both beautiful and fleeting. To catch one, you must know how they are formed and be prepared to search them out when the time is right.
Most people stumble across their first frost flower quite by accident. A walk to the mailbox, walking the dog, or some other activity that occurs outdoors on very brisk winter mornings. While researchers debate the exact mechanics of the formation of frost flowers, the basic premise is quite simple. Very cold temperatures force water within the main stem or under the bark of a herbaceous plant to begin to freeze. The plant material cannot contain the expanding water, which has become super-cold and possibly impregnated with ice crystals, but is not yet frozen. Slowly this moisture forces its way out of the plant through one or more cracks, slits or breaks in the outer stem. As the water slowly exits the plant, it freezes entirely, creating layer upon layer of delicate ice ribbons. Like a snowflake, no two frost flowers are ever the same.
While it is not yet known how many species of plants have the ability or tendency to generate frost flowers, a few plants native to the Americas are well-known. Among these are White Crownbeard (Verbesina virginica), which produces rather large frost flowers and Rock Rose (Helianthemum canadense), also known as Frostweed. In the Ozarks we are blessed with an abundance of native forest-dwelling American Dittany (Cunila origanoides), which is known to be a consistent bearer of frost flowers.
Sometimes referred to as wild oregano, dittany is an herbaceous plant that both resembles and smells like true oregano. This diminutive and often overlooked native herb grows up to 10” tall in dry, rocky woods and clearings. It has bright green teardrop-shaped leaves that grow in opposite pairs along wiry, four-sided stems common among plants in the mint family.
In late summer this otherwise unassuming plant explodes with soft round inflorescences of impossibly small, clear-purple flowers born at the leaf axils. Like its cousin oregano, the summer leaves of dittany are wonderfully fragrant and can be used both as a seasoning for food and as a delicate hot tea on cold winter nights. In the fall, dittany enchants with a subtle change in leaf color, turning from bright green to deep purple.
Because of its delicate beauty and usefulness, I have planted dittany in my wild flower garden. As a bonus, this lovely native also affords me many opportunities to witness their miraculous “winter bloom”. The frost flowers of dittany tend to be made up of long, thin, translucent ribbons that are curled and contorted into fantastic shapes of milky white ice striated in horizontal layers. I marvel at their complexity and fragility. If touched, these ephemeral flowers will crumble to bits. Such transitory and rare beauty is what I love about living so closely with nature.
The occurrence of frost flowers is hard to time with any precision. However, when the weather suddenly turns from warm to freezing and there has been a relatively good amount of moisture preceding the temperature change, chances are good for spotting one of these beauties. Early morning hikes in open woodland are best for hunting frost flowers, for the moment the sun touches them, these fleeting flowers return to the earth from which they came.