Plant Profiles

January Gifts from The Garden

Carolina or Yellow Jessamine ( Gelsemium sempervirens )

By Janet Grabowski

As we start the new year, we will soon see canary yellow flowers scattered on the walkways in the hammock area of the Garden. Garden visitors have asked me if these flowers are coming from the trees. I tell them, “No, that they are produced by the woody vines (or lianas) that are climbing up the trees”. These vines are Carolina or yellow jessamine plants.  

When Carolina jessamine is growing in shady areas, like the hammock, the vines will climb up to 25 feet high into the tree canopy to reach more light. Because the plants are long-lived, the stems can reach almost an inch in diameter. When growing in sunny areas, the vines will ramble along on top of the ground. Carolina jessamine is sometimes used as a ground cover in areas where foot traffic is not anticipated. 

These vines can also be planted where they can twine up an adjacent trellis or fence. There are Carolina jessamine vines growing on the chain link fence in the Garden as well as the ones clambering up the trees. 

The opposite leaves of Carolina jessamine are mostly lance-shaped to somewhat rounded. They are shiny, dark green and evergreen, hence the species name sempervirens, which translates to always (semper) and green (virens).  

The flowers are held in the axils of the leaves and are either solitary or in small clusters. They are 1 to 2 inches in length, tubular in shape and flare out into five rounded lobes at the mouth of the flower. They are highly fragrant and attract pollinators such as bees, butterflies, and hummingbirds. The flowering period starts in January, when few other flowering plants are available to feed pollinators, and continues through March.  The fruit is a capsule that contains numerous flat, winged seeds.

All parts of this plant are poisonous, containing alkaloids that are related to strychnine. Many types of livestock are susceptible to poisoning by this plant. This danger is greatest in the winter, when livestock are attracted to its evergreen leaves. Cases of human poisoning have also been reported, often because individuals confuse this plant with honeysuckle (Lonicera spp,) and they ingest nectar from the flowers. The sap of Carolina jessamine plants can also be a skin irritant for sensitive individuals. Despite its toxicity, Carolina jessamine has been used as a component in herbal and homeopathic remedies.

Carolina jessamine is a member of the Gelsemiaceae Family, which is a small family containing only three genera; Gelsemium is the only genus found in the United States. Carolina jessamine plants grow in mesic hammocks, upland pinelands, and ruderal areas in northern and central Florida. In the Panhandle, a related species G. rankinii can be found growing in swampy areas. It has a similar growth habit and appearance to Carolina jessamine, but the leaves are larger.

Further information about Carolina jessamine can be found at these sites:

Carolina jessamine - Florida Wildflower Foundation

Carolina Jessamine – Gardening Solutions, IFAS

Gelsemium sempervirens–  Florida Native Plant Society