The state flower of South Carolina is Gelsemium sempervirens (jel-SEM-ee-um sem-per-VY-renz) an attractive perennial vine whose name translates to “evergreen jasmine.”
However, it is not a true jasmine (sometimes spelled jessamine) despite being part of the Gelsemiaceae family.
The plant has the peculiar nickname of poor man’s rope, which refers to its high toxicity. Other common names include:
- Carolina Jasmine
- Carolina jessamine
- Evening trumpet flower
- False jasmine
- Wild woodbine
- Yellow jessamine
Additionally, it may be found under the alternate scientific name of Bignonia sempervirens due to changes in classification over the years.
Carolina jessamine has a wide natural habitat throughout North America, spanning the southern United States from Florida and Virginia to Texas and Arizona, as well as much of Central America.
It’s a popular ornamental vine, both for its evergreen leaves and bright yellow flowers.
In some parts of Southern US, true yellow jasmine is often confused with Carolina jessamine. The easiest way to tell these two plants apart is the number of stamens.
True jasmine has two, while Carolina jessamine has five. This distinction is vital when there’s a possibility part of the plant has been ingested.
Carolina Yellow Jasmine Care
Size & Growth
Carolina jessamine is a twining vine with thin, reddish-brown woody stems that typically grow 8’ to 12’ feet high, but may achieve heights of 20’ feet or more when clinging to trees and allowed to grow untended.
When grown without support, the plant will form a bushy ground cover with a height of up to 3’ feet, using runners to spread. Growth tends to be moderate until it’s well established.
The waxy, dark green pinnate leaves are 2” to 4” inches long and .4” to .6” inches wide. In the colder regions, the leaves may take on yellow or purple hues during winter months.
Flowering and Fragrance
The main show occurs between February and April, when the plant produces clusters of yellow trumpet-shaped flowers, some of which may have an orange center.
The flowers are approximately 1.2” inches long and have a sweet scent that attracts a variety of pollinators.
In some situations, the plant may enjoy a second bloom time in autumn.
The seeds of this plant are brown capsules, measuring 1.5” inches long.
Light & Temperature
Carolina jasmine prefers full sun, but will tolerate light shade.
The vine is sturdy enough to make it wind tolerant and can handle both cold and brief bouts of heat. It does well in USDA hardiness zones 7 to 10.
Watering and Feeding
This plant requires moderate watering to keep the soil moist. As it has a tap root, it can withstand short periods of drought.
A good palm plant food, will work wonders when used 2 to 3 times during the growing season.
Soil & Transplanting
While Carolina jessamine prefers a rich, organic soil, it can handle a moderate range of soil types and conditions. Everything from clay to sandy soils will work, especially those which are loamy in nature.
Regardless of soil type, the planting space must be well-drained. Carolina jessamine is known to be highly adaptable to different pH conditions.
Grooming And Maintenance
This plant is extremely low-maintenance, although it will spread indefinitely if left untended for long periods of time. You may shape the plant by pruning in early spring, as well as using elastic ties to train the vine.
How To Propagate False Jasmine
Seed capsules become mature in October and November. The contained seeds should be brown.
You can store the seeds by allowing them to dry for a few days before removing the seeds from the capsules, and storing them in a refrigerated, sealed container until needed.
When germinating from seed, it is best to start them off in a greenhouse, separating the seedlings into individual containers.
Once the plants are two years old, they may be transplanted outdoors in early summer.
Hardwood and semi-hardwood cuttings may also be used to propagate, following the same methods as other vine plants.
Carolina Jessamine Main Pest or Disease Problems
Deer avoid this plant. It can also tolerate wind and a moderate amount of salt. It’s mildly drought resistant.
The sap has also been known to cause dermatitis in some individuals. The plant as a whole is also highly flammable.
WARNING: This plant is highly poisonous to both humans and livestock. A single ingested flower is enough to kill a child.
The toxins cause extreme muscle relaxation which eventually results in respiratory arrest. The effects may take up to half an hour, and death occurs in 1 to 7.5 hours if not treated.
When you suspect your or a loved one has ingested parts of this plant, it is important to call a poison center immediately. They will evacuate the stomach if caught early enough.
The patient is kept on artificial respiration while a subcutaneous treatment is administered.
The nectar is toxic to honeybees in sufficient quantities and the honey produced is also toxic.
However, the plant’s nectar is beneficial to bumblebees who have learned to selectively use it to kill parasites, increasing their foraging efficiency.
Suggested Yellow Jessamine Uses
This evergreen vine is highly popular for arbors, archways, trellises, and other structures. It will also twine its way up tree trunks. Its ability to grow without support allows it to cascade along banks and serve as a low-maintenance ground cover.
If left to grow wild, Caroline jessamine will spread indefinitely as thickets, absorbing fences, covering walls, or clinging to trees.
The flowers are sometimes used as a signal that winter is coming to an end. They also attract bees, butterflies, and hummingbirds.
The rhizome of Carolina jessamine has been used in medicine, although its now considered dangerous.
The drug, also called gelsemium, was believed to help with breathing problems such as asthma, migraines, and nerve pain.
While not FDA approved due to lack of evidence to any real benefits, it has been confirmed to be extremely dangerous in any amount for children and pregnancies.