The Night Blooming Jasmine (Cestrum nocturnum) is an ornamental plant known for its intense fragrance, particularly after dusk. Its greenish-white or yellow flowers release an intoxicating scent at night, making this woody shrub a popular choice for gardens and patios. Though commonly called jasmine, this plant is a member of the nightshade family, Solanaceae.
Ideal Growing Temperatures
Night Blooming Jasmine thrives in consistently warm conditions, preferring temperatures ranging from 68 to 100°F (20 to 38°C). As a native of tropical and subtropical regions, it prefers heat and high humidity. Maintaining temperatures within this optimal range promotes vigorous growth and abundant flowering.
For optimal bloom production, an ideal range is 65-85°F (18-29°C). Slight temperature fluctuations can encourage more blooms. While the plant tolerates some variation, stable warm temperatures support its overall health and bloom cycles. Consistent warmth supports the prolific blooms that release its signature nocturnal fragrance.
Cold Tolerance and Winter Protection
Night Blooming Jasmine is sensitive to cold temperatures and is not frost-hardy. Established plants may tolerate brief dips as low as 25°F (-4°C), but new growth is vulnerable below 35°F (2°C). Temperatures approaching freezing, specifically below 40-45°F (4-7°C), can cause significant damage. Frost exposure often results in leaves turning brown or black, wilting, drooping, and stem dieback.
In cooler climates outside USDA Hardiness Zones 8-11, winter protection is necessary. Potted Night Blooming Jasmine should be moved indoors before the first frost, ideally to a bright, south-facing window. Indoors, maintain temperatures between 59-75°F (15-24°C), avoiding drafts or direct heat sources like vents. For outdoor plants in borderline zones, apply a thick layer of mulch around the base to insulate roots. Covering the plant with a frost blanket during unexpected cold snaps offers further protection.
Heat Tolerance and Summer Care
Night Blooming Jasmine handles high temperatures well, given its tropical origins. However, extreme heat, particularly consistent temperatures above 90-95°F (32-35°C), can induce stress. Signs of heat stress include wilting, leaf scorch (where leaves may lighten in color), and reduced blooming. If temperatures exceed 110°F (43°C), leaves can become lighter and more susceptible to sunburn.
To mitigate heat stress in hot climates, several care practices are important. Adequate and consistent watering is crucial, as the plant requires more moisture in hot, dry conditions. Providing afternoon shade can shield the plant from intense sun. Ensuring good air circulation also helps prevent overheating.
Addressing Temperature Stress
When Night Blooming Jasmine shows signs of temperature stress, immediate steps can aid recovery. Assess the damage, then prune away any blackened, brown, or wilted leaves and dead stems. This removes compromised tissue, allowing the plant to redirect energy to healthy growth. After pruning, gradually reintroduce the plant to more favorable conditions.
For plants moved indoors due to cold, ensure they receive bright, indirect light and stable temperatures, avoiding sudden changes. If heat-stressed, move the plant to a shadier location. Proper watering is important; stressed plants should not be overwatered, as this can lead to root rot. Instead, maintain consistently moist, but not soggy, soil.