The most fundamental difference in care stems from their distinct botanical lineages. Common Jasmine (Jasminum officinale) is a true jasmine, a deciduous or semi-evergreen climbing vine from the Oleaceae family. It grows rapidly with long, pliable stems that twine around supports. In contrast, Star Jasmine (Trachelospermum jasminoides) is not a true jasmine but an evergreen woody vine or ground cover from the Apocynaceae family. Its growth is more controlled and shrub-like, with stems that produce a milky sap and cling via aerial roots, making it an excellent choice for covering walls or sprawling across the ground.
Their tolerance to cold is a critical factor in care and placement. Common Jasmine is moderately hardy, typically surviving in USDA zones 7-10. It can withstand winter temperatures down to about 10°F (-12°C) but may die back to the ground in colder zones, often regrowing from the roots in spring. Star Jasmine is slightly more cold-tolerant, thriving in zones 8-10 and often surviving in zone 7 with protection. It can handle brief dips to around 5°F (-15°C). As an evergreen, it retains its foliage year-round in milder climates, whereas Common Jasmine will lose its leaves in colder winters.
Both plants enjoy ample sunlight for optimal flowering, but their ideal exposure differs. Common Jasmine performs best in full sun to partial shade. It requires a minimum of 4-6 hours of direct sunlight daily to produce its prolific and famously fragrant white blossoms. Star Jasmine is more adaptable to varying light conditions. It thrives in full sun but is also one of the best flowering vines for partial shade and can even tolerate heavy shade, though this will significantly reduce its flowering. In very hot climates, afternoon shade can prevent leaf scorch.
While both prefer consistently moist, well-drained soil, their watering needs differ slightly, especially when established. Common Jasmine has a moderate thirst and requires regular watering, particularly during its first growing season and periods of drought. Its soil should not be allowed to dry out completely. Star Jasmine is notably more drought-tolerant once its root system is fully established. It can handle short periods of dryness better than Common Jasmine. However, for both species, maintaining even moisture is key to preventing stress, which can lead to bud drop or pest problems.
The timing and technique for pruning are dictated by their flowering habits. Common Jasmine blooms on new growth. The optimal time for pruning is in late winter or early spring, just before new growth begins. This encourages a flush of new vines that will bear that season's flowers. Heavy pruning is well-tolerated. Star Jasmine, however, flowers on previous year's growth (old wood). Pruning should be done immediately after the main spring flowering period has concluded. Pruning in late summer, fall, or winter would remove the developing flower buds, drastically reducing or eliminating blooms the following year.
