The cold winter temperatures may make it seem like spring is a long way off, but before we know it, spring will arrive, bringing warmer temperatures and spring-blooming plants. When we think about spring-blooming plants, many plants may come to mind, including traditional garden favorites, such as daffodils, crocus, tulips, grape hyacinths, or, if natives are your thing, Virginia bluebell, trilliums, and spring beauty. There is one plant that beats all these plants to bloom, often blooming with snow still on the ground: skunk cabbage.
Where is skunk cabbage found, and what does it look like?
Skunk cabbage (Symplocarpus foetidus) is native to eastern North America, including the northern half of Illinois. It grows in wet areas, such as marshy woods, wetlands, stream banks, and bogs. It is among the first, if not the first, plant to bloom in the spring, with flowers emerging as early as February. Like other members of the Arum family, they produce flowers (spadix) that are surrounded by a spathe (a modified leaf).
The spathes are 4 to 6 inches tall, hood-like, and often twisted. They can range in color from wine red to marron, and some may have yellow to yellow-green mottling and streaking. The spadix is 2 to 5 inches long with a number of tightly packed flowers. The female flowers will mature before the male flowers do.
As their name implies, skunk cabbage has unpleasant smelling flowers that have been described as smelling like skunk and putrid meat, while others describe it as smelling like garlic or a mix of cabbage and mustard.
As the spathe begins to wilt, leaves will emerge from the rhizomes. The leaves form a funnel-shaped rosette and can reach 3 feet long and 1 foot wide. When damaged, the leaves also have a skunk-like odor. The leaves also contain calcium oxalate crystals that cause a burning sensation when eaten. By the time summer arrives, the leaves will begin to die and will break down rapidly.
The plant that generates heat
Perhaps the most notable attribute of skunk cabbage is that it is one of the few plants that can generate its own heat. The heat is produced by the spadix as it breaks down starches. The plants are capable of maintaining temperatures inside the spathe 15-35+°F (documented to over 80°F) warmer than the surrounding air temperature.
There are several theories as to why skunk cabbage evolved to generate its own heat.
- The heated air helps spread the odor of the flower, attracting pollinators.
- Plants will produce more heat while the female flowers are mature, allowing pollination to be more successful.
- The heat can also help attract insect visitors, protecting them from low temperatures and increasing the amount of time they visit their flowers, potentially increasing pollination.
Skunk cabbage may not be a typical garden ornamental, but its early bloom time and unusual biology make it a fascinating native plant worth appreciating, whether in the wild or, for the adventurous gardener, in a home wetland garden.
Good Growing Fact of the Week: Skunk cabbage uses the reaction of starch and oxygen to produce heat. It is estimated that skunk cabbages consume as much oxygen as mammals of the same size.
By Ken Johnson, Horticulture Educator, University of Illinois Extension
