Carolina jessamine is a perennial, climbing vine native to Central and North America, growing wild from Guatemala to the southeastern US. Its Latin name is Gelsemium sempervirens, and it is the state flower of South Carolina. Carolina Jessamine has thin, twining, reddish stems and can easily grow 10-20 feet (3-6 m) tall when climbing up trees, walls or other forms of support. Its oblong, green, glossy leaves are 2-4 inches (5-10 cm) long, and its large, bright yellow flowers are trumpet-shaped, sometimes with orange centers. All parts of the plant, including the sap and nectar, contain toxic alkaloids that can cause skin irritations, convulsions and respiratory failure.
Carolina jessamine is also known by several other names: yellow jessamine, Carolina yellow jasmine, false jasmine, evening trumpetflower and woodbine. The word jessamine is a variation on jasmine and many of these names are inspired by the plant's strongly scented flowers. The blooms appear in mid-spring to mid-summer, and attract butterflies and many other insects.
Carolina jessamine is a common garden plant in many US states from Florida to Virginia and west into Arkansas and Texas. It is often used to cover fences, arbors and trellises. When growing untended in shadier areas such as pine forests, it can climb high on trees or other structures, searching for sunlight. In areas with full sun, Carolina jessamine can be grown as a low-maintenance groundcover, for example on steep slopes, but it has to be pruned hard or mowed to keep the vines from forming mounds. It can also be grown in containers, for example on a deck or patio.
This low-maintenance plant grows best in full sun to light shade and requires well-drained soil and regular watering, though established plants are able to tolerate drought. To promote more blooms, it is recommended to grow Carolina jessamine in full sun and to fertilize it sparingly. It is hardy to 15 degrees Fahrenheit (-9 degrees C) and can tolerate frost, but not extended periods of freezing temperatures. Its leaves stay green year round, but might look droopy and wilted in cold or dry weather.
This plant is easy to propagate. Cuttings can be taken in spring, or the root ball can be divided and replanted. Carolina jessamine can also be grown from seed, and one can collect seeds from the plant's dry seed pods in the fall for this purpose. The plant grows vigorously once established and if needed should be pruned back immediately after flowering.