Our native Carolina Jessamine, Gelsemium sempervirens, is a spectacular ornamental vine that is well-known throughout the South. Its range is from Virginia to Texas and southward through Mexico. Another species, Gelsemium rankinii, also known as Swamp Jessamine, is native to the Southeast. A relative, Gelsemium elegans, also a climbing vine, is native to India, parts of China and Southeast Asia. Gelsemium sempervirens translated from Latin means "evergreen jasmine". The common name, Jessamine, is a variant spelling of Jasmine. "Jasmine" is of Persian origin, meaning "God's gift." It must be noted, however, that Gelsemium species are not among what some consider to be "true jasmine" of the genus Jasminum.
Carolina Jessamine foliage (about 1" to 4" long) is elongated. Whether it is evergreen depends upon the climate. It is semi-evergreen in northern parts of its range. Beautiful fragrant yellow flowers, 1-1/2" long and tubular, appear in early spring and sometimes in fall creating elegant garlands of yellow on arbors and pergolas. Motorists are sure to notice it as they travel along our highways as Jessamine festoons trees and shrubs. Mature height as a ground cover is only 24", but when allowed to climb, it will just keep on going.
Carolina Jessamine is cold-hardy in USDA climate zones 7 through 9. It flowers best in full sun, but will grow in full sun or shade in well-drained soil with average to poor fertility. Recommended soil pH covers a wide range: from 5.5 to 8.5. If planted in shade, it will find something to climb until it enjoys sunlight. Plants are drought tolerant when established, and heat-loving.
Because the flowers are beautiful and abundant, Gelsemium is usually planted with that purpose in mind. Unlike some other ornamental vines, it does not attach itself permanently to its support. Gelsemium ascends by twining around the support. For that reason, if grown on a wall, it will need a trellis to climb upon. If necessary, it can be pruned back drastically in order to maintain supporting walls, trellises, pergolas, arbors, mail boxes and light posts.
Gelsemium can be effective as a ground cover for erosion control in small to large areas. If allowed to grow as a ground cover, it will certainly do so, but will climb the first chance it gets.
It must be noted that in spite of its loveliness, Carolina Jessamine is highly toxic if eaten. So don't. The good news is that it is deer-resistant.
Prepare the planting bed for Gelsemium sempervirens by cultivating at least 6" deep, removing all traces of weeds. Compacted soil should be cultivated to 12" deep. Add enough soil to raise the bed at least 4" above the surrounding ground level. This will help to promote good drainage. Composted manure may be incorporated into the soil. Fertilizer may be used. If you choose to do so, incorporate 5-10-15 fertilizer at a rate of no more 2 lbs. per 100 square feet into the top 4" to 6" of soil. Avoid synthetic fertilizers contacting any part of your plants.
Plant at 24" to 48" spacing. Dig planting holes into the cultivated soil a little less deep than the depth of the growing container. Place the plants into the holes and back-fill, watering as you go. Press soil around the roots. Do not cover the root balls with soil. The tops should be slightly exposed. Add a top-dressing of mulch around the plants, not on top of them, about 2" deep.
To encourage plant density and more profuse bloom, prune Gelsemium occasionally, especially if grown as a ground cover. Edging around the perimeter of the ground cover bed and shearing the top is very effective. Though Carolina Jessamine vines are capable of growing 20' high, they can be grown in containers on trellises of 3' to 4' and maintained by pruning.
Carolina Jessamine is one of my favorite flowering vines. It can be grown high or low, over your mailbox or under it. The deep yellow garlands in the trees drop lovely blossoms on the forest floor below, golden mantles drape garden walls, and the fragrance is wonderful.
Return to Gelsemium at goGardenNow.com.